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': 'Limit of eccentricity of air rotor bur is \nSelect and explain. \nA. 0.01 mm, B. 0.04 mm, C. 0.02 mm, D. 0.03 mm', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]