What is true of most crustal rocks?

Question

A. They were formed from chemical or biochemical precipitates.
B. They were formed from compacted sediments.
C. They solidified from a molten state.
D. They were metamorphosed by heat and pressure under the earth's surface.

Answer 1

D

Answer 2

Your question may be put this way :
What is the most abundant rock in the earth's crust
A. Chemical/biochemical sediments
B. Sedimentary rocks
C. Igneous rocks
D.Metamorphic rocks.
A. Chemical or Biochemical sedimentary rocks occur in in minor quantity and hence they are not a competitor.
B. Sedimentary rocks, although occur in larger quantities than chemical and biochemical sediments, they are often metamorphosed and should be categorised under D.
C. Igneous rocks (volcanic, Plutonic & hypobyssal) are truely the dominant rock type in the earth's crust. But in most places they are metamorphosed.
D. Hence these should be considered as the predominant rock type in the earth's crust.