单项选择题

A.Mad+Cad+Had+Oad+Nad+Sc,ad=100%
B.Car+Har+Oar+Nar+Sc,ar=100%
C.Cdaf+Hdaf+Odaf+Sc,daf+Ndaf=100%
D.Cd+Hd+Nd+Ad+Od=100%