Which term refers to rocks created through the cooling of magma or lava?

The term that refers to rocks created through the cooling of magma or lava is igneous. Igneous rocks are formed when molten rock material, or magma, cools and solidifies either beneath the Earth’s surface (intrusive igneous rocks) or on the surface after a volcanic eruption (extrusive igneous rocks). This process involves the crystallization of minerals as the magma or lava cools, resulting in the formation of diverse rock types with different chemical compositions and textures, such as granite and basalt.

Understanding the categories of rock types can help clarify why igneous is the appropriate choice. Sedimentary rocks, for instance, form through the accumulation and compaction of sediments, often in water bodies, over time. Metamorphic rocks arise from the alteration of existing rock types due to heat, pressure, or chemically active fluids, without the rock melting entirely. The term crystalline, while it can describe certain textures within some rocks, does not specifically refer to the rock formation process involving magma or lava. Thus, igneous is the most fitting term to describe rocks that originate directly from the cooling of molten rock.