— Will you go shopping with me tomorrow?

— I’d like to, but I am too busy. If you don’t mind, Susan will go ________ me.

A．instead

B．instead of

C．on

D．with

为了使稀介质浓缩后溢流带走的磁性物少，（）磁性物在浓缩机中的沉降。

A.加速

B.减缓

C.阻止

D.防止