This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Chemotherapy, Subject name: Pharmacology
All are alkylating agents except 
Select and explain. 
A. 5 flurouracil, B. Melphalan, C. Cycloohosphamide, D. Chlorambucil
A: 5 flurouracil
Answer: A: 5 flurouracil 
Explanation: Refer Katzung 11/e p945 5 flurouracil is an Antimetabolite whereas Melphalan Cyclophosphamide .chlorambucil These are alkylating agents