对危重病人正确的做法是（）。

A.必须仔细问诊，以免误诊

B.简要问诊，重点体检，迅速抢救

C.全面体检，收集完整资料

D.等待化验结果，然后治疗

E.立即转院

All flights       because of the snowstorm,we decided to take the train. [ ]

A.were canceled

B.had been canceled

C.having canceled

D.having been canceled