Acting on the recommendation of a British government committee investigating the high incidence in white lead factories of illness among employees, most of who were women, the Home Secretary proposed in 1895 that Parliament enact legislation that would prohibit women from holding most jobs in white lead factories. Although the Women's Industrial Defense Committee (WIDC), formed in 1892 in response to earlier legislative attempts to restrict women's labor, did not discount the white lead trade's potential health dangers, it opposed the proposal, viewing it as yet another instance of limiting women's work opportunities. Also opposing the proposal was the Society for Promoting the Employment of Women (SPEW), which attempted to challenge it by investigating the causes of illness in white lead factories. SPEW contended, and WIDC concurred, that controllable conditions in such factories were responsible for the development of lead poisoning. SPEW provided convincing evidence that lead poisoning could be avoided if workers were careful and clean and if already extant workplace safety regulations were stringently enforced. However, the Women's Trade Union League (WTUL), which had ceased in the late 1880s to oppose restrictions on women's labor, supported the eventually enacted proposal, in part because safety regulations were generally not being enforced in white lead factories, where there were no unions (and little prospect of any) to pressure employers to comply with safety regulations.

The passage suggests that WIDC differed from WTUL in which of the following ways?

Acting on the recommendation of a British government committee investigating the high incidence in white lead factories of illness among employees, most of who were women, the Home Secretary proposed in 1895 that Parliament enact legislation that would prohibit women from holding most jobs in white lead factories. Although the Women's Industrial Defense Committee (WIDC), formed in 1892 in response to earlier legislative attempts to restrict women's labor, did not discount the white lead trade's potential health dangers, it opposed the proposal, viewing it as yet another instance of limiting women's work opportunities. Also opposing the proposal was the Society for Promoting the Employment of Women (SPEW), which attempted to challenge it by investigating the causes of illness in white lead factories. SPEW contended, and WIDC concurred, that controllable conditions in such factories were responsible for the development of lead poisoning. SPEW provided convincing evidence that lead poisoning could be avoided if workers were careful and clean and if already extant workplace safety regulations were stringently enforced. However, the Women's Trade Union League (WTUL), which had ceased in the late 1880s to oppose restrictions on women's labor, supported the eventually enacted proposal, in part because safety regulations were generally not being enforced in white lead factories, where there were no unions (and little prospect of any) to pressure employers to comply with safety regulations.

Which of the following, if true, would most clearly support the contention attributed to SPEW in highlighted text?

Acting on the recommendation of a British government committee investigating the high incidence in white lead factories of illness among employees, most of who were women, the Home Secretary proposed in 1895 that Parliament enact legislation that would prohibit women from holding most jobs in white lead factories. Although the Women's Industrial Defense Committee (WIDC), formed in 1892 in response to earlier legislative attempts to restrict women's labor, did not discount the white lead trade's potential health dangers, it opposed the proposal, viewing it as yet another instance of limiting women's work opportunities. Also opposing the proposal was the Society for Promoting the Employment of Women (SPEW), which attempted to challenge it by investigating the causes of illness in white lead factories. SPEW contended, and WIDC concurred, that controllable conditions in such factories were responsible for the development of lead poisoning. SPEW provided convincing evidence that lead poisoning could be avoided if workers were careful and clean and if already extant workplace safety regulations were stringently enforced. However, the Women's Trade Union League (WTUL), which had ceased in the late 1880s to oppose restrictions on women's labor, supported the eventually enacted proposal, in part because safety regulations were generally not being enforced in white lead factories, where there were no unions (and little prospect of any) to pressure employers to comply with safety regulations.

The passage is primarily concerned with

Acting on the recommendation of a British government committee investigating the high incidence in white lead factories of illness among employees, most of who were women, the Home Secretary proposed in 1895 that Parliament enact legislation that would prohibit women from holding most jobs in white lead factories. Although the Women's Industrial Defense Committee (WIDC), formed in 1892 in response to earlier legislative attempts to restrict women's labor, did not discount the white lead trade's potential health dangers, it opposed the proposal, viewing it as yet another instance of limiting women's work opportunities. Also opposing the proposal was the Society for Promoting the Employment of Women (SPEW), which attempted to challenge it by investigating the causes of illness in white lead factories. SPEW contended, and WIDC concurred, that controllable conditions in such factories were responsible for the development of lead poisoning. SPEW provided convincing evidence that lead poisoning could be avoided if workers were careful and clean and if already extant workplace safety regulations were stringently enforced. However, the Women's Trade Union League (WTUL), which had ceased in the late 1880s to oppose restrictions on women's labor, supported the eventually enacted proposal, in part because safety regulations were generally not being enforced in white lead factories, where there were no unions (and little prospect of any) to pressure employers to comply with safety regulations.

According to the passage, the WIDC believed that the proposed legislation resembled earlier legislation concerning women’s labor in that it

In 1955 Maurice Duverger published The Political Role of Women, the first behavioralist, multinational comparison of women’s electoral participation ever to use election data and survey data together. His study analyzed women’s patterns of voting, political candidacy, and political activism in four European countries during the first half of the twentieth century. Duverger’s research findings were that women voted somewhat less frequently than men (the difference narrowing the longer women had the vote) and were slightly more conservative.

Duverger’s work set an early standard for the sensitive analysis of women’s electoral activities. Moreover, to Duverger’s credit, he placed his findings in the context of many of the historical processes that had shaped these activities. However, since these contexts have changed over time, Duverger’s approach has proved more durable than his actual findings. In addition, Duverger’s discussion of his findings was hampered by his failure to consider certain specific factors important to women’s electoral participation at the time he collected his data: the influence of political regimes, the effects of economic factors, and the ramifications of political and social relations between women and men. Given this failure, Duverger’s study foreshadowed the enduring limitations of the behavioralist approach to the multinational study of women’s political participation.

The primary purpose of the passage is to

In 1955 Maurice Duverger published The Political Role of Women, the first behavioralist, multinational comparison of women’s electoral participation ever to use election data and survey data together. His study analyzed women’s patterns of voting, political candidacy, and political activism in four European countries during the first half of the twentieth century. Duverger’s research findings were that women voted somewhat less frequently than men (the difference narrowing the longer women had the vote) and were slightly more conservative.

Duverger’s work set an early standard for the sensitive analysis of women’s electoral activities. Moreover, to Duverger’s credit, he placed his findings in the context of many of the historical processes that had shaped these activities. However, since these contexts have changed over time, Duverger’s approach has proved more durable than his actual findings. In addition, Duverger’s discussion of his findings was hampered by his failure to consider certain specific factors important to women’s electoral participation at the time he collected his data: the influence of political regimes, the effects of economic factors, and the ramifications of political and social relations between women and men. Given this failure, Duverger’s study foreshadowed the enduring limitations of the behavioralist approach to the multinational study of women’s political participation.

According to the passage, Duverger's study was unique in 1955 in that it

In 1955 Maurice Duverger published The Political Role of Women, the first behavioralist, multinational comparison of women’s electoral participation ever to use election data and survey data together. His study analyzed women’s patterns of voting, political candidacy, and political activism in four European countries during the first half of the twentieth century. Duverger’s research findings were that women voted somewhat less frequently than men (the difference narrowing the longer women had the vote) and were slightly more conservative.

Duverger’s work set an early standard for the sensitive analysis of women’s electoral activities. Moreover, to Duverger’s credit, he placed his findings in the context of many of the historical processes that had shaped these activities. However, since these contexts have changed over time, Duverger’s approach has proved more durable than his actual findings. In addition, Duverger’s discussion of his findings was hampered by his failure to consider certain specific factors important to women’s electoral participation at the time he collected his data: the influence of political regimes, the effects of economic factors, and the ramifications of political and social relations between women and men. Given this failure, Duverger’s study foreshadowed the enduring limitations of the behavioralist approach to the multinational study of women’s political participation.

Which of the following characteristics of a country is most clearly an example of a factor that Duverger, as described in the passage, failed to consider in his study?

In 1955 Maurice Duverger published The Political Role of Women, the first behavioralist, multinational comparison of women’s electoral participation ever to use election data and survey data together. His study analyzed women’s patterns of voting, political candidacy, and political activism in four European countries during the first half of the twentieth century. Duverger’s research findings were that women voted somewhat less frequently than men (the difference narrowing the longer women had the vote) and were slightly more conservative.

Duverger’s work set an early standard for the sensitive analysis of women’s electoral activities. Moreover, to Duverger’s credit, he placed his findings in the context of many of the historical processes that had shaped these activities. However, since these contexts have changed over time, Duverger’s approach has proved more durable than his actual findings. In addition, Duverger’s discussion of his findings was hampered by his failure to consider certain specific factors important to women’s electoral participation at the time he collected his data: the influence of political regimes, the effects of economic factors, and the ramifications of political and social relations between women and men. Given this failure, Duverger’s study foreshadowed the enduring limitations of the behavioralist approach to the multinational study of women’s political participation.

The author implies that Duverger’s actual findings are

In 1955 Maurice Duverger published The Political Role of Women, the first behavioralist, multinational comparison of women’s electoral participation ever to use election data and survey data together. His study analyzed women’s patterns of voting, political candidacy, and political activism in four European countries during the first half of the twentieth century. Duverger’s research findings were that women voted somewhat less frequently than men (the difference narrowing the longer women had the vote) and were slightly more conservative.

Duverger’s work set an early standard for the sensitive analysis of women’s electoral activities. Moreover, to Duverger’s credit, he placed his findings in the context of many of the historical processes that had shaped these activities. However, since these contexts have changed over time, Duverger’s approach has proved more durable than his actual findings. In addition, Duverger’s discussion of his findings was hampered by his failure to consider certain specific factors important to women’s electoral participation at the time he collected his data: the influence of political regimes, the effects of economic factors, and the ramifications of political and social relations between women and men. Given this failure, Duverger’s study foreshadowed the enduring limitations of the behavioralist approach to the multinational study of women’s political participation.

The passage implies that, in comparing four European countries, Duverger found that the voting rates of women and men were most different in the country in which women

In 1955 Maurice Duverger published The Political Role of Women, the first behavioralist, multinational comparison of women’s electoral participation ever to use election data and survey data together. His study analyzed women’s patterns of voting, political candidacy, and political activism in four European countries during the first half of the twentieth century. Duverger’s research findings were that women voted somewhat less frequently than men (the difference narrowing the longer women had the vote) and were slightly more conservative.

Duverger’s work set an early standard for the sensitive analysis of women’s electoral activities. Moreover, to Duverger’s credit, he placed his findings in the context of many of the historical processes that had shaped these activities. However, since these contexts have changed over time, Duverger’s approach has proved more durable than his actual findings. In addition, Duverger’s discussion of his findings was hampered by his failure to consider certain specific factors important to women’s electoral participation at the time he collected his data: the influence of political regimes, the effects of economic factors, and the ramifications of political and social relations between women and men. Given this failure, Duverger’s study foreshadowed the enduring limitations of the behavioralist approach to the multinational study of women’s political participation.

The author implies that some behavioralist research involving the multinational study of women's political participation that followed Duverger's study did which of the following?

By the sixteenth century, the Incas of South America ruled an empire that extended along the Pacific coast and Andean highlands from what is now Ecuador to central Chile. While most of the Incas were selfsufficient agriculturists, the inhabitants of the highland basins above 9,000 feet were constrained by the kinds of crops they could cultivate. Whereas 95 percent of the principal Andean food crops can be cultivated below 3,000 feet, only 20 percent reproduce readily above 9,000 feet. Given this unequal resource distribution, highland Incas needed access to the products of lower, warmer climatic zones in order to enlarge the variety and quantity of their foodstuffs. In most of the preindustrial world, the problem of different resource distribution was resolved by long-distance trade networks over which the end consumer exercised little control. Although the peoples of the Andean highlands participated in such networks, they relied primarily on the maintenance of autonomous production forces in as many ecological zones as possible. The commodities produced in these zones were extracted, processed, and transported entirely by members of a single group.

This strategy of direct access to a maximum number of ecological zones by a single group is called vertical economy. Even today, one can see Andean communities maintaining use rights simultaneously to pasturelands above 12,000 feet, to potato fields in basins over 9,000 feet, and to plots of warm-land crops in regions below 6,000 feet. This strategy has two principal variations. The first is “compressed verticality,” in which a single village resides in a location that permits easy access to closely located ecological zones. Different crop zones or pasturelands are located within a few days walk of the parent community. Community members may reside temporarily in one of the lower zones to manage the extraction of products unavailable in the homeland. In the second variation, called the “vertical archipelago,” the village exploits resources in widely dispersed locations, constituting a series of independent production “islands.” In certain pre-Columbian Inca societies, groups were sent from the home territory to establish permanent satellite communities or colonies in distant tropical forests or coastal locations. There the colonists grew crops and extracted products for their own use and for transshipment back to their high-altitude compatriots. In contrast to the compressed verticality system, in this system, commodities rather than people circulated through the archipelago.

According to the passage, which of the following is true about the pre-industrial long distance trade networks mentioned in line 22 ?

By the sixteenth century, the Incas of South America ruled an empire that extended along the Pacific coast and Andean highlands from what is now Ecuador to central Chile. While most of the Incas were selfsufficient agriculturists, the inhabitants of the highland basins above 9,000 feet were constrained by the kinds of crops they could cultivate. Whereas 95 percent of the principal Andean food crops can be cultivated below 3,000 feet, only 20 percent reproduce readily above 9,000 feet. Given this unequal resource distribution, highland Incas needed access to the products of lower, warmer climatic zones in order to enlarge the variety and quantity of their foodstuffs. In most of the preindustrial world, the problem of different resource distribution was resolved by long-distance trade networks over which the end consumer exercised little control. Although the peoples of the Andean highlands participated in such networks, they relied primarily on the maintenance of autonomous production forces in as many ecological zones as possible. The commodities produced in these zones were extracted, processed, and transported entirely by members of a single group.

This strategy of direct access to a maximum number of ecological zones by a single group is called vertical economy. Even today, one can see Andean communities maintaining use rights simultaneously to pasturelands above 12,000 feet, to potato fields in basins over 9,000 feet, and to plots of warm-land crops in regions below 6,000 feet. This strategy has two principal variations. The first is “compressed verticality,” in which a single village resides in a location that permits easy access to closely located ecological zones. Different crop zones or pasturelands are located within a few days walk of the parent community. Community members may reside temporarily in one of the lower zones to manage the extraction of products unavailable in the homeland. In the second variation, called the “vertical archipelago,” the village exploits resources in widely dispersed locations, constituting a series of independent production “islands.” In certain pre-Columbian Inca societies, groups were sent from the home territory to establish permanent satellite communities or colonies in distant tropical forests or coastal locations. There the colonists grew crops and extracted products for their own use and for transshipment back to their high-altitude compatriots. In contrast to the compressed verticality system, in this system, commodities rather than people circulated through the archipelago.

According to the passage, the inhabitants of the Andean highlands resolved the problem of unequal resource distribution primarily in which of the following ways?

By the sixteenth century, the Incas of South America ruled an empire that extended along the Pacific coast and Andean highlands from what is now Ecuador to central Chile. While most of the Incas were selfsufficient agriculturists, the inhabitants of the highland basins above 9,000 feet were constrained by the kinds of crops they could cultivate. Whereas 95 percent of the principal Andean food crops can be cultivated below 3,000 feet, only 20 percent reproduce readily above 9,000 feet. Given this unequal resource distribution, highland Incas needed access to the products of lower, warmer climatic zones in order to enlarge the variety and quantity of their foodstuffs. In most of the preindustrial world, the problem of different resource distribution was resolved by long-distance trade networks over which the end consumer exercised little control. Although the peoples of the Andean highlands participated in such networks, they relied primarily on the maintenance of autonomous production forces in as many ecological zones as possible. The commodities produced in these zones were extracted, processed, and transported entirely by members of a single group.

This strategy of direct access to a maximum number of ecological zones by a single group is called vertical economy. Even today, one can see Andean communities maintaining use rights simultaneously to pasturelands above 12,000 feet, to potato fields in basins over 9,000 feet, and to plots of warm-land crops in regions below 6,000 feet. This strategy has two principal variations. The first is “compressed verticality,” in which a single village resides in a location that permits easy access to closely located ecological zones. Different crop zones or pasturelands are located within a few days walk of the parent community. Community members may reside temporarily in one of the lower zones to manage the extraction of products unavailable in the homeland. In the second variation, called the “vertical archipelago,” the village exploits resources in widely dispersed locations, constituting a series of independent production “islands.” In certain pre-Columbian Inca societies, groups were sent from the home territory to establish permanent satellite communities or colonies in distant tropical forests or coastal locations. There the colonists grew crops and extracted products for their own use and for transshipment back to their high-altitude compatriots. In contrast to the compressed verticality system, in this system, commodities rather than people circulated through the archipelago.

The passage suggests that as a way of addressing the problem of different resource distribution in the preindustrial world, the practice of vertical economy differed from the use of longdistance trade networks in that vertical economy allowed

By the sixteenth century, the Incas of South America ruled an empire that extended along the Pacific coast and Andean highlands from what is now Ecuador to central Chile. While most of the Incas were selfsufficient agriculturists, the inhabitants of the highland basins above 9,000 feet were constrained by the kinds of crops they could cultivate. Whereas 95 percent of the principal Andean food crops can be cultivated below 3,000 feet, only 20 percent reproduce readily above 9,000 feet. Given this unequal resource distribution, highland Incas needed access to the products of lower, warmer climatic zones in order to enlarge the variety and quantity of their foodstuffs. In most of the preindustrial world, the problem of different resource distribution was resolved by long-distance trade networks over which the end consumer exercised little control. Although the peoples of the Andean highlands participated in such networks, they relied primarily on the maintenance of autonomous production forces in as many ecological zones as possible. The commodities produced in these zones were extracted, processed, and transported entirely by members of a single group.

This strategy of direct access to a maximum number of ecological zones by a single group is called vertical economy. Even today, one can see Andean communities maintaining use rights simultaneously to pasturelands above 12,000 feet, to potato fields in basins over 9,000 feet, and to plots of warm-land crops in regions below 6,000 feet. This strategy has two principal variations. The first is “compressed verticality,” in which a single village resides in a location that permits easy access to closely located ecological zones. Different crop zones or pasturelands are located within a few days walk of the parent community. Community members may reside temporarily in one of the lower zones to manage the extraction of products unavailable in the homeland. In the second variation, called the “vertical archipelago,” the village exploits resources in widely dispersed locations, constituting a series of independent production “islands.” In certain pre-Columbian Inca societies, groups were sent from the home territory to establish permanent satellite communities or colonies in distant tropical forests or coastal locations. There the colonists grew crops and extracted products for their own use and for transshipment back to their high-altitude compatriots. In contrast to the compressed verticality system, in this system, commodities rather than people circulated through the archipelago.

The passage suggests that for an Andean highland village attempting to resolve the problem of unequal resource distribution, the strategy known as compressed verticality would probably be inappropriate for which of the following situations?

By the sixteenth century, the Incas of South America ruled an empire that extended along the Pacific coast and Andean highlands from what is now Ecuador to central Chile. While most of the Incas were selfsufficient agriculturists, the inhabitants of the highland basins above 9,000 feet were constrained by the kinds of crops they could cultivate. Whereas 95 percent of the principal Andean food crops can be cultivated below 3,000 feet, only 20 percent reproduce readily above 9,000 feet. Given this unequal resource distribution, highland Incas needed access to the products of lower, warmer climatic zones in order to enlarge the variety and quantity of their foodstuffs. In most of the preindustrial world, the problem of different resource distribution was resolved by long-distance trade networks over which the end consumer exercised little control. Although the peoples of the Andean highlands participated in such networks, they relied primarily on the maintenance of autonomous production forces in as many ecological zones as possible. The commodities produced in these zones were extracted, processed, and transported entirely by members of a single group.

This strategy of direct access to a maximum number of ecological zones by a single group is called vertical economy. Even today, one can see Andean communities maintaining use rights simultaneously to pasturelands above 12,000 feet, to potato fields in basins over 9,000 feet, and to plots of warm-land crops in regions below 6,000 feet. This strategy has two principal variations. The first is “compressed verticality,” in which a single village resides in a location that permits easy access to closely located ecological zones. Different crop zones or pasturelands are located within a few days walk of the parent community. Community members may reside temporarily in one of the lower zones to manage the extraction of products unavailable in the homeland. In the second variation, called the “vertical archipelago,” the village exploits resources in widely dispersed locations, constituting a series of independent production “islands.” In certain pre-Columbian Inca societies, groups were sent from the home territory to establish permanent satellite communities or colonies in distant tropical forests or coastal locations. There the colonists grew crops and extracted products for their own use and for transshipment back to their high-altitude compatriots. In contrast to the compressed verticality system, in this system, commodities rather than people circulated through the archipelago.

According to the passage, Inca inhabitants of the highland basins above 9,000 feet were limited by which of the following?

By the sixteenth century, the Incas of South America ruled an empire that extended along the Pacific coast and Andean highlands from what is now Ecuador to central Chile. While most of the Incas were self-sufficient agriculturists, the inhabitants of the highland basins above 9,000 feet were constrained by the kinds of crops they could cultivate. Whereas 95 percent of the principal Andean food crops can be cultivated below 3,000 feet, only 20 percent reproduce readily above 9,000 feet. Given this unequal resource distribution, highland Incas needed access to the products of lower, warmer climatic zones in order to enlarge the variety and quantity of their foodstuffs. In most of the preindustrial world, the problem of different resource distribution was resolved by long-distance trade networks over which the end consumer exercised little control. Although the peoples of the Andean highlands participated in such networks, they relied primarily on the maintenance of autonomous production forces in as many ecological zones as possible. The commodities produced in these zones were extracted, processed, and transported entirely by members of a single group.

This strategy of direct access to a maximum number of ecological zones by a single group is called vertical economy. Even today, one can see Andean communities maintaining use rights simultaneously to pasturelands above 12,000 feet, to potato fields in basins over 9,000 feet, and to plots of warm-land crops in regions below 6,000 feet. This strategy has two principal variations. The first is “compressed verticality,” in which a single village resides in a location that permits easy access to closely located ecological zones. Different crop zones or pasturelands are located within a few days walk of the parent community. Community members may reside temporarily in one of the lower zones to manage the extraction of products unavailable in the homeland. In the second variation, called the “vertical archipelago,” the village exploits resources in widely dispersed locations, constituting a series of independent production “islands.” In certain pre-Columbian Inca societies, groups were sent from the home territory to establish permanent satellite communities or colonies in distant tropical forests or coastal locations. There the colonists grew crops and extracted products for their own use and for transshipment back to their high-altitude compatriots. In contrast to the compressed verticality system, in this system, commodities rather than people circulated through the archipelago.

Which of the following best describes the function of the highlighted sentence?

Although some progress has been made in the last two decades on the treatment of Alzheimer’s disease, the causes of the disease are still largely unknown. A recent study conducted by the National Institute of Aging (NIA) appears to have found new evidence concerning the origins of Alzheimer’s. Scientists who carried out the study at NIA focused on the correlation between a patient’s genetic history, which scientists usually agree is the basis of Alzheimer’s, and the onset of Alzheimer’s. The evidence cited by the NIA team includes the identification of the apolipoprotein E (APOE) as the specific gene that may be responsible for the onset of Alzheimer’s. The APOE gene can be sub-divided into many different forms, but the NIA research team has identified one specific form of APOE, the APOE ?4 gene, as a very likely cause of Alzheimer’s. The presence of APOE ?4 is known to make an individual particularly vulnerable to both cognitive and vascular dysfunction, which are among the chief symptoms of Alzheimer’s.

However, a review of the study and its results by the Center for Disease Control and Prevention (CDC) maintains that the evidence discovered by the NIA may not necessarily indicate that the APOE ?4 gene is responsible for Alzheimer’s. CDC experts have pointed out that APOE ?4 is known to cause conditions such as cardiac disease and diabetes in patients who have no genetic history of Alzheimer’s and are not considered at risk for the disease. Further, the CDC review team has observed that APOE ?4 has been found in individuals who show no symptoms of Alzheimer’s. In response to the CDC’s review, the NIA team has pointed out that the APOE ?4 gene may be dormant in some individuals, suggesting that the absence of Alzheimer’s in individuals who have the APOE ?4 gene cannot be used as evidence to rule out this gene as the cause of Alzheimer’s disease.

The primary purpose of the passage is to

Although some progress has been made in the last two decades on the treatment of Alzheimer’s disease, the causes of the disease are still largely unknown. A recent study conducted by the National Institute of Aging (NIA) appears to have found new evidence concerning the origins of Alzheimer’s. Scientists who carried out the study at NIA focused on the correlation between a patient’s genetic history, which scientists usually agree is the basis of Alzheimer’s, and the onset of Alzheimer’s. The evidence cited by the NIA team includes the identification of the apolipoprotein E (APOE) as the specific gene that may be responsible for the onset of Alzheimer’s. The APOE gene can be sub-divided into many different forms, but the NIA research team has identified one specific form of APOE, the APOE ?4 gene, as a very likely cause of Alzheimer’s. The presence of APOE ?4 is known to make an individual particularly vulnerable to both cognitive and vascular dysfunction, which are among the chief symptoms of Alzheimer’s.

However, a review of the study and its results by the Center for Disease Control and Prevention (CDC) maintains that the evidence discovered by the NIA may not necessarily indicate that the APOE ?4 gene is responsible for Alzheimer’s. CDC experts have pointed out that APOE ?4 is known to cause conditions such as cardiac disease and diabetes in patients who have no genetic history of Alzheimer’s and are not considered at risk for the disease. Further, the CDC review team has observed that APOE ?4 has been found in individuals who show no symptoms of Alzheimer’s. In response to the CDC’s review, the NIA team has pointed out that the APOE ?4 gene may be dormant in some individuals, suggesting that the absence of Alzheimer’s in individuals who have the APOE ?4 gene cannot be used as evidence to rule out this gene as the cause of Alzheimer’s disease.

The author makes which of the following statements about the relevance of genetic history as the basis of Alzheimer’s disease?

Although some progress has been made in the last two decades on the treatment of Alzheimer’s disease, the causes of the disease are still largely unknown. A recent study conducted by the National Institute of Aging (NIA) appears to have found new evidence concerning the origins of Alzheimer’s. Scientists who carried out the study at NIA focused on the correlation between a patient’s genetic history, which scientists usually agree is the basis of Alzheimer’s, and the onset of Alzheimer’s. The evidence cited by the NIA team includes the identification of the apolipoprotein E (APOE) as the specific gene that may be responsible for the onset of Alzheimer’s. The APOE gene can be sub-divided into many different forms, but the NIA research team has identified one specific form of APOE, the APOE ?4 gene, as a very likely cause of Alzheimer’s. The presence of APOE ?4 is known to make an individual particularly vulnerable to both cognitive and vascular dysfunction, which are among the chief symptoms of Alzheimer’s.

However, a review of the study and its results by the Center for Disease Control and Prevention (CDC) maintains that the evidence discovered by the NIA may not necessarily indicate that the APOE ?4 gene is responsible for Alzheimer’s. CDC experts have pointed out that APOE ?4 is known to cause conditions such as cardiac disease and diabetes in patients who have no genetic history of Alzheimer’s and are not considered at risk for the disease. Further, the CDC review team has observed that APOE ?4 has been found in individuals who show no symptoms of Alzheimer’s. In response to the CDC’s review, the NIA team has pointed out that the APOE ?4 gene may be dormant in some individuals, suggesting that the absence of Alzheimer’s in individuals who have the APOE ?4 gene cannot be used as evidence to rule out this gene as the cause of Alzheimer’s disease.

Which of the following claims does the NIA support by providing the information that the APOE ?4 gene may be dormant in some individuals?

Although some progress has been made in the last two decades on the treatment of Alzheimer’s disease, the causes of the disease are still largely unknown. A recent study conducted by the National Institute of Aging (NIA) appears to have found new evidence concerning the origins of Alzheimer’s. Scientists who carried out the study at NIA focused on the correlation between a patient’s genetic history, which scientists usually agree is the basis of Alzheimer’s, and the onset of Alzheimer’s. The evidence cited by the NIA team includes the identification of the apolipoprotein E (APOE) as the specific gene that may be responsible for the onset of Alzheimer’s. The APOE gene can be sub-divided into many different forms, but the NIA research team has identified one specific form of APOE, the APOE ?4 gene, as a very likely cause of Alzheimer’s. The presence of APOE ?4 is known to make an individual particularly vulnerable to both cognitive and vascular dysfunction, which are among the chief symptoms of Alzheimer’s.

However, a review of the study and its results by the Center for Disease Control and Prevention (CDC) maintains that the evidence discovered by the NIA may not necessarily indicate that the APOE ?4 gene is responsible for Alzheimer’s. CDC experts have pointed out that APOE ?4 is known to cause conditions such as cardiac disease and diabetes in patients who have no genetic history of Alzheimer’s and are not considered at risk for the disease. Further, the CDC review team has observed that APOE ?4 has been found in individuals who show no symptoms of Alzheimer’s. In response to the CDC’s review, the NIA team has pointed out that the APOE ?4 gene may be dormant in some individuals, suggesting that the absence of Alzheimer’s in individuals who have the APOE ?4 gene cannot be used as evidence to rule out this gene as the cause of Alzheimer’s disease.

Which of the following best describes the function of the first sentence of the second paragraph?