This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other topics and Adverse effects, Subject name: Pharmacology
[{'content': 'Resistance to acyclovir is most commonly due to mutation in a viral gene that encodes a protein that: \nSelect and explain. \nA. Conves viral RNA into DNA, B. Phosphorylates acyclovir, C. transpos acyclovir into the cell, D. Transpos acyclovir out of the cell', 'role': 'user'}, {'content': 'Answer: B \nExplanation: (Ref: KDT 6/e p768) Nucleoside/tide analogues (like acyclovir) act by conveing to NTPs. First phosphorylation step occurs inside the virs and resistance occurs if there is mutation in this gene.', 'role': 'assistant'}]