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
E antigen (HBeAg) of hepatitis B virus is a product of which gene 
Select and explain. 
A. S, B. C, C. p, D. x
B: C
Answer: B: C 
Explanation: Ans. is 'b' i.e., C Genes & gene products The genome of HBV is made of circular DNA, but it is unusual because the DNA is not fully double stranded --> one of the strands is incomplete and other is complete - paially double stranded DNA. There are four known genes encoded by genome --> 'C' , X', `P' ,'S'.