若，，下列式子成立的是(    )．
   (A)
   (B)
   (C)
   (D)

A.174.24.96:6088/Latex/latex.action?latex=XGxpbSBfe3hcdG8geF8wfWYoeCk9XGluZnR5IA%3D%3D'
B.174.24.96:6088/Latex/latex.action?latex=XGxpbSBfe3hcdG8geF8wfWcoeCk9XGluZnR5IA%3D%3D'
C.

D.174.24.96:6088/Latex/latex.action?latex=XGxpbSBfe3hcdG8geF8wfVtmKHgpK2coeCldPVxpbmZ0eSA%3D'
E.174.24.96:6088/Latex/latex.action?latex=XGxpbSBfe3hcdG8geF8wfVtmKHgpLWcoeCldPVxpbmZ0eSA%3D'
F.174.24.96:6088/Latex/latex.action?latex=XGxpbSBfe3hcdG8geF8wfVxmcmFjezF9e2YoeCkrZyh4KX09MA%3D%3D'
G.174.24.96:6088/Latex/latex.action?latex=XGxpbSBfe3hcdG8geF8wfVxmcmFjezF9e2YoeCl9PTA%3D'