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': 'On a carbide bur, a great number of cutting blades results in: \nSelect and explain. \nA. Less efficient cutting and a smoother surface, B. Less efficient cutting and a rougher surface, C. More efficient cutting and a smoother surface, D. More efficient cutting and a rougher surface', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]