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
Which of the following markers in the blood is the most reliable indicator of recent hepatitis B infection? 
Select and explain. 
A. HBsAg, B. IgG anti - HBs, C. IgM anti HBc, D. IgM anti - HBe
C: IgM anti HBc
Answer: C: IgM anti HBc 
Explanation: None