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
20-year-old boy has admitted with history of fever, icterus, conjunctival suffusion and hematuria for 20 days. Which of the following serological test can be of diagnostic utility: 
Select and explain. 
A. Widal test, B. Microscopic agglutination test, C. Paul-Bunnell-test, D. Weil-Felix reaction
B: Microscopic agglutination test
Answer: B: Microscopic agglutination test 
Explanation: Ans. is. (b) Microscopic agglutination test