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
A dental bur cuts the tooth structure more effectively when rake angle of bur is 
Select and explain. 
A. Positive, B. Negative, C. Radial, D. None of the above
A: Positive
Answer: A: Positive 
Explanation: None