Which term refers to a category of rocks formed from a molten state?

Which term refers to a category of rocks formed from a molten state?

• A. IndN
• B. Indicator minerals
• C. Habit
• D. Igneous

Answer: (D)

Rocks formed from molten material are igneous rocks. When rock material melts into magma and later cools and solidifies, crystals form and the rock becomes igneous. If cooling happens slowly underground, you get coarse-grained rocks like granite; if it happens quickly at the surface, you get fine-grained rocks like basalt or glassy textures like obsidian. Other terms here refer to different ideas—indicator minerals are clues used in exploration, and crystal habit describes the common shape of crystals—which aren’t about how rocks originated from a molten state. So the term that specifically names rocks formed from a molten state is igneous.

Rocks formed from molten material are igneous rocks. When rock material melts into magma and later cools and solidifies, crystals form and the rock becomes igneous. If cooling happens slowly underground, you get coarse-grained rocks like granite; if it happens quickly at the surface, you get fine-grained rocks like basalt or glassy textures like obsidian. Other terms here refer to different ideas—indicator minerals are clues used in exploration, and crystal habit describes the common shape of crystals—which aren’t about how rocks originated from a molten state. So the term that specifically names rocks formed from a molten state is igneous.