This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anti-Viral Drugs, Subject name: Pharmacology
[{'content': 'Which of the following antiviral drugs is used against HCV infection? \nSelect and explain. \nA. Acyclovir, B. Sofosbuvir, C. Oseltamivir, D. Adefovir', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Sofosbuvir is a direct acting anti-viral drug used against HCV infection. It is a nucleotide analog that inhibits HCV RNA polymerase (NS-5B). The active from of sofosbuvir competes with uridine triphosphate for incorporation into HCV RNA by NS5B polymerase. -Acyclovir: DOC for Herpes simplex virus 1 and 2 and also DOC for varicella zoster -Oseltamivir: DOC for bird flu and swine flu -Adefovir: Primarily used for HBV infection', 'role': 'assistant'}]