—What volunteer work would you like to do?

—I'd like to              sick people in the hospital. [ ]

A. turn up

B. stay up

C. look up

D. cheer up

购买动机是指消费者为了满足某种（）产生购买活动的欲望和意念。

A、心愿

B、情感

C、需要

D、心理