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
For air blasting of ceramic veneer the particle size of alumina is used 
Select and explain. 
A. 25 micrometer, B. 50 micrometer, C. 75 micrometer, D. 100 micrometer
B: 50 micrometer
Answer: B: 50 micrometer 
Explanation: None