This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other FP Methods and New Initiatives in Family Planning, Subject name: Social & Preventive Medicine
A man underwent vasectomy, but 6 months later his wife was 16 weeks pregnant. What is the most likely cause? 
Select and explain. 
A. Failure of operative procedure, B. Pregnancy antedating vasectomy, C. Recanalization of vas, D. Failure to use additional contraception in postoperative period
A: Failure of operative procedure
Answer: A: Failure of operative procedure 
Explanation: - Misidentification of Vas deferens by Surgeon is the MCC of Failure in Vasectomy.