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': 'Normal thickness of hybrid layer is: \nSelect and explain. \nA. 0.1-5 micron, B. 2-3 micron, C. 0.5-2 micron, D. 5-10 micron', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]