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': 'The percentage of inorganic matter in fully developed enamel is about \nSelect and explain. \nA. 66%, B. 76%, C. 86%, D. 96%', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Enamel contains 96% of inorganic material and 4% of organic material. The inorganic material is mainly composed of hydroxyappatite crystals.', 'role': 'assistant'}]