This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Virology, Subject name: Microbiology
Acute Hepatitis B can be earliest diagnosed by? 
Select and explain. 
A. IgM anti HBc ab, B. Hbs Ag, C. IgC anti HBc abs, D. Anti HBs Ag ab
A: IgM anti HBc ab
Answer: A: IgM anti HBc ab 
Explanation: For the diagnosis of HBV infection detection of HBsAg in the blood is all that ordinarily necessary. The simultaneous presence of IgM anti-HBc indicates recent infection.occassionally when the level of HBsAg is too low to be detectable, the diagnosis has to be made by testing for IgM anti-HBc. REF:ANANTHANARAYAN AND PANIKER'S TEXTBOOK OF MICROBIOLOGY 9TH EDITION PAGE NO-547