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': 'Reversal lines are a coating found in bone is produced by \nSelect and explain. \nA. Osteoblasts, B. Fibroblasts, C. Osteoclasts, D. Cementoblasts', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]