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: Radiology
[{'content': 'Months or years following radiotherapy, the irradiated oral mucosa \nSelect and explain. \nA. Undergoes necrosis, B. Develops candidiasis, C. Becomes atrophic, D. Develops granulomatosis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]