Igneous rocks have been formed by
A)cooling from a molten state.
B)precipitation from solution.
C)the alteration of other rocks by heat.
D)the alteration of other rocks by pressure.

Question

Quizplus · Accepted Answer

Igneous rocks are formed from the cooling and solidification of molten material, either magma or lava, which is why the correct choice is A. Precipitation from solution (B) refers to sedimentary rocks, while alteration by heat (C) and alteration by pressure (D) are processes involved in the formation of metamorphic rocks.

Igneous Rocks Have Been Formed by