You are presented with the quiz "What can can break down rocks from larger wholes into smaller pieces?" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "weathering means breaking down rocks from larger whole into smaller pieces by weather" and "climates with freeze and thaw promote mechanical weathering". 

So, what's the best answer to the question?


 

   Freezing and thawing        