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': 'Trimethoprim acts by: \nSelect and explain. \nA. Inhibiting peptidyl transferase enzyme, B. Inhibiting dihydrofolate reductase enzyme, C. Inhibiting Dihydropteroate synthase enzyme, D. Binds to 50s ribosomal unit and prevents protein synthesis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Trimethoprim, Methotrexate and pyrimethamine inhibits dihydrofolate reductase enzyme and prevents formation of Tetrahydrofolic acid and from Dihydrofolic acid.', 'role': 'assistant'}]