下列说法中，错误的是（　　）

A．自行车、汽车的轮胎上凹凸不平的花纹是为了增大摩擦力

B．刀刃磨得很薄是为了使用时增大压强

C．人造地球卫星在绕地球从近地点向远地点运行的过程中，重力势能转化为动能

D．手举杠铃不动，手没有对杠铃做功

I could not persuade him to accept it,（）make him see the importance of it.

A. if only I could not

B. or I could not

C. not more than I could

D. nor could I