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
RK - 39 antigen testing is done in 
Select and explain. 
A. Kala azar, B. Chagas disease, C. African sleeping sickness, D. American sleeping sickness
A: Kala azar
Answer: A: Kala azar 
Explanation: RK - 39 test is a Immunochromatographic test done in Kala azar.