It’s _________ of Amy to make the birthday card than ________ one.

A．much clever, to buy

B．cleverer, to buy

C．cleverer, buying

D．most clever, buy

关于房室交界区性逸搏错误的是（）.

A.与房室交界区自律性增高有关

B.是一种生理保护机制

C.房室传导阻滞时可出现

D.与迷走神经张力增高有关

E.显著窦性心动过缓时可出现