Solved UPSC CDS/OTA Question
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Q · Mineralsmedium · 45s
Which type of rock is formed from the cooling and solidification of magma?
TopicMinerals
Question Typemultiple choice
Difficultymedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Igneous rocks form when magma or lava cools and solidifies. This process can occur below Earth's surface (intrusive/plutonic rocks like granite) or on the surface (extrusive/volcanic rocks like basalt). The cooling rate affects crystal size: slow cooling allows large crystals to form, while rapid cooling produces fine-grained or glassy textures. Igneous rocks make up most of Earth's crust and mantle.
Final Answer: Option C - Igneous