<prompt> Semen analysis of a male of an infertile couple shows the absence of spermatozoa but the presence of fructose. The most probable diagnosis is:Prostatic infectionMumps orchitisBlock in efferent duct systemAll of the above  <response>: The efferent ducts may be obstructed by an infection like tubercular, gonococcal or by surgical trauma following vasectomy.The absence of fructose suggests the congenital absence of seminal vesicle or portion of the ductal system or both 