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What is Most common site of ulcerative colitis is? and explain in detail?
ANSWER: (A) RectumREF: Harrison s 18th ed ch: 295UC is a mucosal disease that usually involves the rectum and extends proximally to involve all or part of the colon. About 40-50% of patients have disease limited to the rectum and rectosigmoid, 30-40% have disease extending beyond the sigmoid but not involving the whole colon, and 20% have a total colitis