Which type of rock results from the cooling of molten material?

Igneous rock is formed through the cooling and solidification of molten material, either magma beneath the Earth's surface or lava that cools on the surface after a volcanic eruption. When magma cools slowly underground, it results in coarse-grained igneous rocks, while lava that cools quickly results in fine-grained rocks. This process is fundamental to the rock cycle and distinguishes igneous rocks from other types, such as sedimentary rocks, which are formed from the accumulation of sediments, and metamorphic rocks, which originate from pre-existing rocks that undergo transformation due to heat and pressure. Crystalline rock is a broader category that often describes igneous or metamorphic rocks that have a well-defined crystal structure, but it doesn’t specifically refer to rocks formed by cooling molten material. Therefore, igneous rock is the most accurate answer to the question regarding the origin of rocks from molten material.