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 of the following fulfil all the criterias of Koch's postulates? 
Select and explain. 
A. Treponema pallidum, B. Mycobacterium leprae, C. N. gonorrhoeae, D. None of the above
D: None of the above
Answer: D: None of the above 
Explanation: None