鉴别室速与阵发性室上速最有力的证据是（）

A.QRS波群宽大畸形的程度

B.是否存在房室分离

C.心室率的快慢

D.静脉应用普罗帕酮是否可终止

E.对迷走神经刺激的反应

Logbooks are used to record the events occurring when（）.

A.the ship is in a harbor

B.the ship is at anchorage

C.the ship is underway

D.All of the above