A student wonders if shale and sandstone can be classified as igneous, metamorphic, or sedimentary. Which information will best help the students answer this question?

A.
the size and alignment of the shale and sandstone crystals

B.
the types of minerals found in shale and sandstone

C.
the places where shale and sandstone are found

D.
the processes that cause shale and sandstone to form

D. the processes that cause shale and sandstone to form