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 used in the treatment of angiofibroma when it involves - \nSelect and explain. \nA. Cheek, B. Orbit, C. Middle cranial fossa, D. Cavernous sinus', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Radiotherapy in JNA is used :-\n\n\nVery rarely as a primary mode of treatment\nFor intracranial extension, e.g., middle cranial fossa\nFor recurrent angiofibroma (internal modulated radiotherapy)', 'role': 'assistant'}]