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: Anatomy
[{'content': 'Ganciclovir is preferred over acyclovir in the following condition \nSelect and explain. \nA. Herpes simplex keratitis, B. Herpes zoster, C. Chicken pox, D. Cytomegalovirus retinitis in AIDs patients', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ref-KDT 6/e p769 Ganciclovir is the drug of choice for CMV infections. Acyclovir is highly effective against Herpes simplex and Varicellal zoster (chicken pox and herpes zoster) but it has very little activity against CMV.', 'role': 'assistant'}]