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
[{'content': 'All are dihydrofolate reductase antagonists, EXCEPT- \nSelect and explain. \nA. Methotrexate, B. Cytosine arabinoside, C. Pentamidine, D. Pyrimethamine', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Cytosine Arabinoside Dihydrofolate reductase antagonists are o Methotreyate o Pentamidine o Trimethoprim o Pyrimetham ne", 'role': 'assistant'}]