Hiking trips ________ sound exciting to most kids, but few realize they ________ be uncomfortable

and even dangerous. [ ]

A. may; can  

B. must; should

C. would; should  

D. can; will

男性，42岁。会阴和肛门周围瘙痒剧烈、糜烂，部分皮疹呈苔藓样变，病史3年，应诊断（）

A. * * 外湿疹样癌

B.扁平苔藓

C.会阴瘙痒症

D.会阴、阴囊和肛门湿疹

E.白塞病