用同一张底片对着小球运动的路径每隔s拍一次照，得到的照片如图所示，则小球在图中过程运动的平均速度大小是

A．0.25 m/s        

B．0.2 m/s

C．0.17 m/s  

D．无法确定

---The exam was easy, wasn’t it?

---Yes, but I don’t think _________ could pass it.

A．somebody

B．anybody

C．nobody

D．everybody