insects eating a dead tree a bulldozer pushing soil ice fracturing a stone acid rain dissolving limestone
I gave my students this multiple choice question: Which of these is the best example of physical weathering?

Only one answer is correct among these 4 choices:
- insects eating a dead tree
- a bulldozer pushing soil
- ice fracturing a stone
- acid rain dissolving limestone

Could you tell me which one is correct?

ice fracturing a stone