膀胱内药物灌注，目前认为效果最好的是（）。

A.噻替哌

B.丝裂霉素

C.阿霉素

D.卡介苗

E.羟基喜树碱

The place _______ the bridge is supposed to be built should be _______ the cross-river traffic is the heaviest.

A．which; where

B．at which; which

C．at which; where

D．which; in which