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 drug DOES NOT cause megaloblastic anemia? 
Select and explain. 
A. Phenytoin, B. Chloroquine, C. Sulfasalazine, D. Metformin
B: Chloroquine
Answer: B: Chloroquine 
Explanation: Agents implicated in drug induced macrocytic anemia are: Phenytoin Azathioprine Metformin Leflunomide Sulfisoxazole Sulfasalazine Mesalamine Zidovudine Trimethoprim Sulfamethoxazole