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': 'The drug used for first-trimester abortion is: \nSelect and explain. \nA. Oral mifepristone, B. Intra–amniotic saline, C. Extra–amniotic ethacridine lactate, D. Oxytocin infusion', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]