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 among the following is NOT used in leptospirosis? 
Select and explain. 
A. Microscopic agglutination test, B. Dark field illumination, C. Macroscopic agglutination test, D. Weil felix reaction
D: Weil felix reaction
Answer: D: Weil felix reaction 
Explanation: Weil felix reaction