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
The pin diameter of Minim (inch/mm) is: 
Select and explain. 
A. 0.019/0.48, B. 0.024/0.61, C. 0.015/0.38, D. 0.027/0.78
B: 0.024/0.61
Answer: B: 0.024/0.61 
Explanation: None