Rocks formed by the cooling of molten lava are classified as

• A. Sedimentary
• B. Metamorphic
• C. Igneous
• D. Clastic

Answer: (C)

Rocks formed by the cooling of molten material are igneous. This type results when magma or lava cools and solidifies, whether underground (intrusive) or on the surface after an eruption (extrusive). The cooling process crystallizes minerals, with the rate of cooling affecting texture—slow cooling yields coarse grains like granite, while rapid cooling gives fine grains or glassy rocks like obsidian. Sedimentary rocks form from sediments that are deposited and lithified, and metamorphic rocks come from existing rocks altered by heat and pressure without melting. Clastic describes a sedimentary texture made of cemented fragments, not a rock formed by cooling lava. So the correct classification is igneous.