This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
[{'content': 'Which of the following art is a fusion inhibitor? \nSelect and explain. \nA. Zidovudine, B. Enfuvirtide, C. Nevirapine, D. Ritonavir', 'role': 'user'}, {'content': "Answer: B \nExplanation: (Refer: K. D. Tripathi's Essentials of Medical Pharmacology, 7th edition, pg no:774)", 'role': 'assistant'}]