I didn’t see your sister at the meeting. If she ___________, she would have met my brother.

A．has come

B．did come

C．came

D．had come

在露天矿的剥离工程和筑坝工程施工时，通常多采用()施工。

A.预裂爆破法 

B.硐室爆破法 

C.裸露药包法 

D.药壶爆破法