If they spend some time on Chinese history, they will be more able to predict China''s future.

A．more

B．able

C．better

D．better able

胆总管和胰管共同开口于

A．十二指肠上部

B．十二指肠降部

C．十二指肠水平部

D．十二指肠升部

E．十二指肠空肠曲