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
Most important criteria in using irrigating solution is 
Select and explain. 
A. Volume of irrigation, B. Thickness of syringe used, C. Concentration of irrigant, D. None of above
A: Volume of irrigation
Answer: A: Volume of irrigation 
Explanation: None