cracks forming in a boulder rocks melting to form magma glaciers forming on a mountainside pebbles combining to form a large rock
I gave my students this multiple choice question: Which of the following can be caused by weathering?

Only one answer is correct among these 4 choices:
- cracks forming in a boulder
- rocks melting to form magma
- glaciers forming on a mountainside
- pebbles combining to form a large rock

Could you tell me which one is correct?

cracks forming in a boulder