This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Virology, Subject name: Microbiology
[{'content': 'A 32-year-old HIV infected male is noted to have acute CMV infection causing acute gastrointestinal symptoms. The treating physician has ordered antiviral therapy. Which of the following is most likely to be targeted by the antiviral agent \nSelect and explain. \nA. Synthesis of viral DNA, B. Transcription of viral proteins, C. Nuclear transpo of virus, D. Protease cleavage', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ganciclovir has been used primarily to treat severe CMV infections, and its method of action involves inhibition of DNA synthesis.', 'role': 'assistant'}]