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
Which of the following is a protease inhibitor ? 
Select and explain. 
A. Lamivudine, B. Saquinavir, C. Delavirdine, D. Zidovudine
B: Saquinavir
Answer: B: Saquinavir 
Explanation: None