<prompt> A case of vasectomy is said to have failed as the vasectomised person;s wife gives bih to a child ten months after the operation. Which one of the following is the most probable cause?Failure of the husband to use condom after vasectomySurgical failureRecannalisationWife had extramarital contact  <response>: Surgical failure is the reason . Reference:Park;s textbook of preventive and social medicine,K.Park,23rd edition,page no:509. p 