Each of the 400 people received from their boss ______ gift － “Who moved my cheese?” , ______ best-seller in the US, which helped them understand how to deal with changes in their lives and work.

A．the; /

B．a; the

C．a; a

D．the; a

在工作面如果闻到臭鸡蛋气味，基本可以大致判定前方有（）。

A．顶板水

B．老空水

C．底板水

D．陷落柱水