Which of these is an example of a sedimentary rock?

The grains of rock that form sedimentary rocks were formed by weathering and erosion. Which statement is correct?

Sedimentary rock is formed when grains of rock get fixed together by:

Which type of rock is a metamorphic rock?

Metamorphic rocks are formed by the effects of:

Which statement describes some of the ways in which metamorphic rocks are different from sedimentary rocks:

Which one of these is an example of igneous rock:

How is Igneous rock formed?

Which of these is the most porous type of rock?

Which type of rock does not contain crystals?