—Where is Tom?

— Well, he ______ you ______ here．Otherwise he would come down right now．

A．didn’t know; were

B．hasn’t known; are

C．doesn’t know; are

D．hadn’t known; were

线路配置综合重合闸装置且按三相重合闸方式投入，当线路发生永久性单相接地故障时，重合闸动作过程为（）。

A.单相跳闸不重合

B.三相跳闸，延时三相重合，后加速跳三相

C.选跳故障相，瞬时重合单相，后加速跳三相

D.直接跳故障相不重合