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
In a syphilis patient, site which does not help in isolation of organism - 
Select and explain. 
A. Gumma, B. Primary chancre, C. Mucosal patch, D. Maculopapular rash
A: Gumma
Answer: A: Gumma 
Explanation: Demonstration of T.pallidum in gumma is very rare.