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': 'Regeneration in periodontal therapy aims at: \nSelect and explain. \nA. Bone refill, B. Repair of the bony defect, C. Reconstitution of the lost periodontium, D. Removal of the diseased bone', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]