Which of the following is an igneous rock?

• Classification of Rocks:
Igneous Rocks
-Igneous rocks are crystalline solids that form directly from the cooling of magma.
-This is an exothermic process (it loses heat) and involves a phase change from the liquid to the solid state.
-Igneous rocks are given names based upon two things: composition (what they are made of) and texture (how big the crystals are)
-Intrusive igneous rocks crystallize below Earth's surface, and the slow cooling that occurs there allows large crystals to form.
-Examples: diorite, gabbro, granite, pegmatite, and peridotite.
-Extrusive igneous rocks erupt onto the surface, where they cool quickly to form small crystals.
-Some cool so quickly that they form an amorphous glass.
-Examples: andesite, basalt, dacite, obsidian, pumice, rhyolite, scoria, and tuff.
Sedimentary rocks
-Sedimentary rocks are formed by the accumulation of sediments
They are formed by
-Weathering (breccia, conglomerate, sandstone, siltstone, and shale)
-Can form when dissolved material precipitate from solution (Rock salt, iron ore, chert, flint, some dolomites, and some limestones)
-Accumulation of plant or animal debris (coal, some dolomites, and some limestones)
Metamorphic rocks
-Metamorphic rocks have been modified by heat, pressure, and chemical processes, usually while buried deep below Earth's surface.
-Exposure to these extreme conditions has altered the mineralogy, texture, and chemical composition of the rocks.
-Example: gneiss, phyllite, schist, and slate, Marble etc.