This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
In azoospermia, the diagnostic test which can distinguish between testicular failure and obstruction in the vas deferens is: September 2012 
Select and explain. 
A. Estimation of FSH level, B. Estimation of testosterone level, C. Karyotyping, D. FNAC of testes
A: Estimation of FSH level
Answer: A: Estimation of FSH level 
Explanation: A i.e. Estimation of FSH level