human
Question: Biotic forces can cause changes to the surface of Earth. Which is the best example of living organisms causing weathering?

Choices:
A) Beavers building a dam across a stream.
B) Cattle walking and grazing in a grassland.
C) Salmon making nests for their eggs in a stream.
D) Tree seedlings growing and forming cracks in rocks.
gpt
The correct answer is 3: Tree seedlings growing and forming cracks in rocks..