单选题
[2009.10]The profit-sharing plan is designed to ______ the staff to work hard.
A.calculate
B.demonstrate
C.speculate
D.motivate
正确答案：D
答案解析：本题考查词语辨析。【译文】利润共享计划目的是激发员工努力工作。A 计算、估算 B 证实、论证、演示 C思索、推测 D 激励、激发