—Thanks for your help, but can you do me one more favor, please?

—______, sir. What's it then?[ ]

A. It is nothing                    

B. That's right

C. At your service                

D. Never mind

拔出DFCS跳开关时以下哪种方法不正确（）。

A.先AFCSAB.FCCDC后AFCSMCP1（2）

B.先AFCSMCP1（2）后AFCSAFCCDCB.

C.以上都正确

D.以上都不正确