Correct Answer: Igneous

Solution : The correct answer is Igneous rocks .

Earth's crust is majorly made up of igneous rocks, about 75%. During the evolution of the earth in its present form, it underwent a process known as gravitational differentiation. In this, the heavier metals from the earth's crust went inside, and the lighter earth material was thrown up through volcanic activity. It led to the stratification of the earth in its present form, and it is also the reason behind the igneous nature of rocks on the earth's crust.