—How do you deal with their objections to our plan？

—I think we can safely ____ them since our plan is made on a scientific basis.

A．approve

B．dismiss

C．distribute

D．disgust

中滑板丝杠与（）部分由前螺母、螺钉、中滑板、后螺母、丝杠和楔块组成。

A.齿轮

B.挂轮

C.螺母

D.机床