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
Serological marker of infectivity of Hepatitis 'B' is - 
Select and explain. 
A. HBsAg, B. HBeAg, C. IgM anti Hbc, D. HBcAg
B: HBeAg
Answer: B: HBeAg 
Explanation: HBeAg presence indicates high infectivity&indicator of active viral application REF:<\p> ANATHANARAYANAN MICROBIOLOGY NINTH EDITION PAGE.547