cracking a rock and making a U-shaped valley making a dune and making a U-shaped valley making a dune and making a V-shaped valley cracking a rock and making a V-shaped valley
I gave my students this multiple choice question: What are two ways ice can change Earth's surface?

Only one answer is correct among these 4 choices:
- cracking a rock and making a U-shaped valley
- making a dune and making a U-shaped valley
- making a dune and making a V-shaped valley
- cracking a rock and making a V-shaped valley

Could you tell me which one is correct?

cracking a rock and making a U-shaped valley