纠纷发生后，当事人申请仲裁的，应符合的条件不包括( )。

A．当事人双方在纠纷发生前订有仲裁协议或仲裁条款

B．当事人双方有仲裁协议

C．当事人双方有具体的仲裁请求、事实和理由

D．属于仲裁委员会的受理范围

The Russian rocket designer has died. For many years, he ______ as an important assistant to the father of Soviet space program.  

A．serves

B．was serving

C．served

D．has served