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: Medicine
Early diagnosis of acute hepatitis-B infection Is made by 
Select and explain. 
A. Presence of HbeAg in serum, B. Presence of IgM anti-HBc in serum, C. Presence of HbsAg in serum, D. Presence of IgG anti-HBc in serum
B: Presence of IgM anti-HBc in serum
Answer: B: Presence of IgM anti-HBc in serum 
Explanation: None