177k views
4 votes
________________ igneous rocks form from the freezing of lava.

a. Extrusive (volcanic)
b. Intrusive (plutonic)
c. Sedimentary
d. Metamorphic

User Nishkaush
by
7.9k points

1 Answer

5 votes

Final answer:

Extrusive (volcanic) igneous rocks are the correct answer, as they form from the rapid cooling of lava on the Earth's surface, resulting in fine-grained textures.

Step-by-step explanation:

Extrusive (volcanic) igneous rocks form from the freezing of lava after it reaches the Earth's surface. These rocks are characterized by a fine-grained texture because the lava cools relatively quickly in the open air, which does not allow large crystals to form. For example, basalt is a common type of extrusive igneous rock formed from basaltic lava flows.

In contrast, intrusive (plutonic) igneous rocks form when magma cools slowly beneath the Earth's surface, resulting in a coarse-grained texture as larger crystals have time to develop. Granite is a well-known example of an intrusive igneous rock.

Sedimentary rocks and metamorphic rocks are formed through different processes involving deposition, cementation, and alteration of pre-existing rocks through heat and pressure, respectively, but are not the correct answers for rocks formed by the freezing of lava.

User Evangelos
by
8.0k points