Three minutes later, more than ten policemen turned up at the spot　　　the accident happened.

A．which

B．what

C．where

D．that

关于特布他林特点的描述不正确的是（）。

A．作用强大

B．可口服

C．维持久

D．心脏兴奋弱

E．无骨骼肌震颤