China is developing fast. That's ________ I think those of my colleagues who deal with China affairs should visit China.

A．because

B．why

C．when

D．how

氯丙嗪作用机制为（）

A、对心肌有奎尼丁样作用

B、使突触间隙的NA浓度下降

C、阻断N胆碱受体

D、阻断D1、D2受体

E、阻断中枢5-HT受体