—Peter, don't step on the grass.

—____________.[ ]

A. It doesn't matter

B. I can't do it

C. Don't worry

D. Sorry, I won't do it again

制动力的传递和牵引力的传递（）。

A.传递过程一样，方向相反

B.过程一样，方向一样

C.过程不一样，方向相反

D.过程不一样，方向一样