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': 'Most common site of volvulus is: \nSelect and explain. \nA. Ileum, B. Appendix, C. Sigmoid colon, D. Caecum', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. (c) Sigmoid colon', 'role': 'assistant'}]