This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infeility (Eggs'plantation!), Subject name: Gynaecology & Obstetrics
Semen analysis sample of male paner of an infeile couple shows low volume with azoospermia and absent fructose. Serum FSH levels are normal. The most probable diagnosis is ? 
Select and explain. 
A. Prostatic infection, B. Mumps orchitis, C. Block in the efferent duct system, D. Hypothalamic dysfunction
C: Block in the efferent duct system
Answer: C: Block in the efferent duct system 
Explanation: Condition Semen Analysis Prostatic Infection Sperms will be present. Increased WBC level purulent semen Mumps orchitis Oligo, astheno and teratospermia Hypothalamic dysfunction Low FSH, azoospermia or oligozoospermia Block in efferent ducts will lead to low volume semen, azoospermia on semen analysis and absent frustose. Normal fructose and sperms can be seen on testicular biopsy.