question number 2 of 40 - earth science\nsome extrusive igneous rocks, such as obsidian, are glassy because…

question number 2 of 40 - earth science\nsome extrusive igneous rocks, such as obsidian, are glassy because they -\nf have low melting points\ng are made of only one mineral\nh cool rapidly\ni contain water
Answer
Brief Explanations:
Extrusive igneous rocks form when magma erupts onto the Earth's surface. Rapid cooling on the surface prevents large - crystal formation, resulting in a glassy texture like in obsidian.
Answer:
H. cool rapidly