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
All of the following drug is CYP3A inhibitor except- 
Select and explain. 
A. Erythromycin, B. Itraconazole, C. Ritonavir, D. Saquinavir
D: Saquinavir
Answer: D: Saquinavir 
Explanation: Ans. is 'd' i.e., Saquinavir