This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Intestinal obstruction, Subject name: Surgery
[{'content': "All are predisposing factors for sigmoid volvulus except: \nSelect and explain. \nA. Hirschsprung's diseases, B. Chagas diseases, C. Chronic constipation, D. Tuberculosis", 'role': 'user'}, {'content': "Answer: D \nExplanation: Hirschsprung's disease and Chagas disease can lead to megacolon, a risk factor for sigmoid volvulus.", 'role': 'assistant'}]