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: Microbiology
The best diagnostic procedure of M.tuberculosis 
Select and explain. 
A. PCR, B. Auramin rhodamin stain, C. Sputum culture, D. ESR
C: Sputum culture
Answer: C: Sputum culture 
Explanation: Ans. is 'c' i.e., Sputum culture "Definitive diagnosis depends on isolation (culture) and identification of M. tuberculosis from a diagnostic sepcimen (most common specimen in sputum)".