He told me that he preferred           at home rather than           out of a walk. [ ]

A. to stay; go

B. to stay; going

C. stayi ng; go

D. staying; to go

肛裂形成的直接原因为（）

A.肛管皮下脓肿破溃

B.干硬粪团致肛管皮肤撕裂

C.长时间腹泻致机械性创伤

D.肛管齿状线附近慢性炎症

E.局部解剖因素