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: Pharmacology
Lamivudine acts at which of the following enzymes? 
Select and explain. 
A. DNA polymerase, B. Reverse transcriptase, C. Both of the above, D. None of the above
C: Both of the above
Answer: C: Both of the above 
Explanation: Lamivudine inhibits HBV DNA polymerase and HIV reverse transcriptase by competing with deoxycytidine triphosphate for incorporation into the viral DNA, resulting in chain termination. Lamivudine achieves 3-4 log decreases in viral replication in most patients and suppression of HBV DNA to undetectable levels in about 44% of patients. Ref: Katzung 11th edition Chapter 49.