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: Dental
[{'content': 'Gingivectomy is contraindicated in: \nSelect and explain. \nA. Gingival hyperplasia, B. Suprabony defects, C. Infrabony pockets, D. Phenytoin induced gingival hyperplasia', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]