This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Surgery
[{'content': 'Most common site of bleeding diveicula \nSelect and explain. \nA. Sigmoid colon, B. Descending colon, C. Rectum, D. Ascending colon', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Diveicula most commonly affect the sigmoid colon and are confined to sigmoid colon in approximately 50% of patients with diveiculosis. Segment of sigoid colon is having smallest luminal diameter, and so colonic pressure as high as 90mm Hg can be generated. Reference : Sabiston, Textbook of Suregery, 19th Edition, page no = 1310.', 'role': 'assistant'}]