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: ENT
[{'content': 'Radiotherapy is the treatment of choice for: \nSelect and explain. \nA. Nasopharyngeal Ca T3 N1, B. Supraglottic Ca T3N0, C. Glottic Ca T3N1, D. Subglottic Ca T3N0', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]