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': 'In breast Ca 6 cm with fixed ipsilateral axillary lymphnode. The TNM staging is : \nSelect and explain. \nA. T3N2, B. T2N2, C. T4N2, D. T1N1', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]