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
[{'content': 'First antibody to appear in blood in Acute Hepatitis B is: \nSelect and explain. \nA. IgM anti-HBc, B. Anti HBs, C. Anti HBe, D. IgG anti HBc', 'role': 'user'}, {'content': 'Answer: A \nExplanation: IgM anti-HBc', 'role': 'assistant'}]