This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hepatitis, Subject name: Medicine
Drug of choice for hepatitis B: 
Select and explain. 
A. Beta interferon, B. Sofosbuvir, C. Simeprevir, D. Tenofovir
D: Tenofovir
Answer: D: Tenofovir 
Explanation: Tenofovir is a first-line agent in the treatment of hepatitis B. It prevents the formation of 5' to 3' phosphodiester linkage essential for DNA chain elongation. Hence it causes premature termination of DNA transcription.