如图，静止的小球分别与两个物体（或面）接触，设各接触面光滑，则小球受到两个或两个以上弹力的是（　　）

A．

B．

C．

D．

Who is responsible for quality management in the project ？（）

A．Project leade

B．Quality control departmen

C．Project manage

D．Team membe