Speaker A: Look, it's going to storm. Take my umbrella. Speaker B: ______

A．How will you go home if you give it to me

B．I have a raincoat in my office. Thanks anyway.

C．I think you need to use it yourself.

D．It doesn't matter. I will go without having your umbrella.

下列哪些情况可有P-R间期延长

A.迷走神经紧张时

B.药物作用，洋地黄

C.急性风湿性心肌炎

D.慢性冠状动脉供血不全

E.房间隔缺损