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': 'The most common reason for the removal of impacted mandibular third molars: \nSelect and explain. \nA. Referred pain, B. Orthodontic treatment, C. Recurrent pericoronitis, D. Chronic periodontal disease', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]