急性下壁心肌梗死最容易并发的心律失常是（）

A.室性心动过速

B.房室传导阻滞

C.房性心动过速

D.心房颤动

E.心室颤动

You have made a few spelling mistakes in your composition but ________, it's well written.[      ]

A. first of all  

B. on the whole

C. on the other hand  

D. after all