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: Pathology
A person(HBs Ag negative) who has received the full course of Vaccine against HBV wants to know the response of vaccine. He should be suggested testing of this serological marker 
Select and explain. 
A. HBs Ag, B. Anti-HBs Ag, C. IgM anti-HBc, D. HBe Ag
B: Anti-HBs Ag
Answer: B: Anti-HBs Ag 
Explanation: Anti HBs is the protective antibody , It is present either after recovery from hepatitis B or immunization.