What is a common characteristic of volcanic rocks?

• A. They form deep underground
• B. They have a coarse-grained texture
• C. They can form from lava cooling quickly
• D. They are all sedimentary

Answer: (C)

Volcanic rocks are formed from the solidification of molten material, specifically lava, which is expelled during volcanic eruptions. When this lava cools quickly on the Earth's surface, it leads to the formation of volcanic rocks that often exhibit a fine-grained texture because the rapid cooling does not allow large crystals to develop. This characteristic is distinctive of volcanic rocks, setting them apart from other rock types that may form from slower cooling processes, typically deep underground.

The other options provide characteristics of different rock types or processes that are not applicable to volcanic rocks specifically, emphasizing why the ability of volcanic rocks to form from rapidly cooling lava is a defining aspect of their identity.