Mr. Crossett ___ his old friend when they met at the railway station.

A．shakes hand with

B．shakes hands with

C．shook hand with

D．shook hands with

男，28岁，近半年来腹泻与便秘交替发生，近3个月来腹部隐痛，近2天解鲜血便，腹部触诊和直肠指诊未发现肿块，钡灌肠示降结肠肠壁僵硬，可见充盈缺损。应诊断为（）

A.乙状结肠癌

B.直肠壶腹癌

C.肠结核

D.溃疡性结肠炎（增殖型）

E.降结肠癌