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 cause myelosuppression except : 
Select and explain. 
A. Docetaxel, B. Vincristine, C. Methotrexate, D. Irinotecan
B: Vincristine
Answer: B: Vincristine 
Explanation: None