洋地黄中毒所致的心律失常最常见的是

A．房性期前收缩

B．心房颤动

C．房室传导阻滞

D．室上性心动过速

E．室性期前收缩

There ________some bread on the table.[ ]

A. is        

B. are          

C. have        

D. has