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: Gynaecology & Obstetrics
[{'content': 'Best prenatal treatment CAH is \nSelect and explain. \nA. Betamethasone, B. Prednisolone, C. Hydrocortisone, D. Dexamethasone', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Prenatal diagnosis of CAH is possible with chorion villus sampling at early weeks of pregnancy using DNA probes\n\nThe 17-OHP level in the amniotic fluid is elevated\nPrenatal therapy with\xa0dexamethasone\xa0or termination of pregnancy is the option', 'role': 'assistant'}]