What are the main types of rocks?

The classification of rocks into igneous, sedimentary, and metamorphic is based on their origin, formation process, and characteristics.

Igneous rocks form from the cooling and solidification of molten material, either magma (beneath the Earth's surface) or lava (on the surface). These rocks can be further divided into intrusive (plutonic) rocks, like granite, which crystallize slowly underground, and extrusive (volcanic) rocks, such as basalt, which solidify quickly at the surface.

Sedimentary rocks develop from the accumulation and compaction of mineral and organic particles. These rocks often form in layers and can contain fossils. Common examples include sandstone, limestone, and shale. Their formation processes often involve weathering, erosion, deposition, and cementation.

Metamorphic rocks arise from existing rocks (either igneous, sedimentary, or other metamorphic rocks) undergoing changes due to heat, pressure, or chemically active fluids. This process alters the mineral composition and texture of the rock, resulting in types such as schist, gneiss, and marble.

Choosing igneous, sedimentary, and metamorphic rocks encompasses the three fundamental types that make up the geological classification, while other choices present specific