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': 'Fluoroquinolones act by which of the following mechanism: \nSelect and explain. \nA. By inhibiting DNA gyrase., B. By inhibiting RNA polymerase., C. Inhibiting folic acid synthesis., D. Inhibiting protein synthesis.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: These drugs act by inhibiting DNA gyrase (topoisomerase II) and topoisomerase IV resulting\xa0in the inhibition of DNA replication.', 'role': 'assistant'}]