You are presented with the quiz "Smaller rocks come from the interaction of bedrock with what over long periods of time" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "rocks interacting with wind over long periods of time causes weathering" and "smaller rocks come from the breakage and weathering of bedrock and larger rocks". 

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


 

  wind         