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
Select the drug that is active against both HIV and hepatitis B virus : 
Select and explain. 
A. Lamivudine, B. Indinavir, C. Didanosine, D. Efavirenz
A: Lamivudine
Answer: A: Lamivudine 
Explanation: None