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
Which organism cannot be cultured in cell free media - 
Select and explain. 
A. Klebsiella rhinoscleromatis, B. Klebsiella ozaenae, C. Treponema pallidum, D. All
C: Treponema pallidum
Answer: C: Treponema pallidum 
Explanation: Ans. is 'c' i.e., Treponema pallidum . Treponema pallidum is an obligate intracellular organism. Thus it cannot be cultivated in cell free medium. . Pneumocystis Jiroveci and Rhinosporidium seeberi can not be cultivated.