---I hate to say it, _______ your car has blocked the way.

--- I’m sorry .I’m about to leave.

A．but

B．and

C．or

D．so

发电机纵联差动保护的动作整定电流大于发电机的额定电流时，应装设电流回路断线监视_装置，短线后动作于信号。