Willpower is a kind of quality, _____ is _____ it takes to do anything well. [ ]

A. what; which

B. what; what

C. which; which

D. which; what

产品的装配工作包括总装配和()。

A、固定式装配 

B、移动式装配 

C、装配顺序 

D、部件装配