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: Pharmacology
[{'content': 'Which among the drugs given below, does NOT act by protease inhibition? \nSelect and explain. \nA. Ritonavir, B. Saquinavir, C. Nelfinavir, D. Zanamivir', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]