— Why didn't you remind him of the possible danger?  

— But what ________ otherwise? He never listens to me. [ ]

A. could I do

B. could I have done

C. should I do    

D. must I have done

男性，32岁，风湿性心脏病心衰用洋地黄和利尿剂治疗，出现恶心、食欲不振，心电图为室性期前收缩二联律。

该患者的可能诊断为（）。

A.肺部感染

B.风湿性心脏病二尖瓣狭窄

C.支气管哮喘

D.急性心包炎

E.风湿性心脏病三尖瓣狭窄