This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': "Jefferson's is : \nSelect and explain. \nA. C1, B. C2, C. C2 C1, D. C2 C3", 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. C1', 'role': 'assistant'}]