This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
Heterophile antibody is found in - 
Select and explain. 
A. Weil Felix test, B. Widal test, C. VDRL, D. All
A: Weil Felix test
Answer: A: Weil Felix test 
Explanation: Weil- Felix reaction for the diagnosis of typhus fever is a hetrophile agglutination test. Based in the sharing of common antigen between typhus rickettsiae and some strains of proteus bacilli. Hetrophile antigen is the same or closely related antigens occurring in different species, classes or kingdoms. Reference : Anathanarayan & paniker's 9th edition, pg no: 109,89 <\p>