This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Contraception, Subject name: Gynaecology & Obstetrics
Failure rate of vasectomy is : 
Select and explain. 
A. 0.20%, B. 0.50%, C. 3%, D. 10%
B: 0.50%
Answer: B: 0.50% 
Explanation: Failure rate us about 0.5% TEXTBOOK OF GYNECOLOGY SHEILA BALAKRISHNAN SECOND EDITION PAGE NO 396