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': 'In Downs syndrome, the 2nd trimester quadruple test done at 14-20 weeks measure levels of all of the following, EXCEPT: \nSelect and explain. \nA. Alpha fetoprotein, B. HCG, C. Inhibin A, D. Progesterone', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The triple test (14 -20 weeks) measures the following three levels in the maternal serum: Alpha-fetoprotein (AFP) Human chorionic gonadotropin (hCG) Unconjugated estriol (UE3) Quadruple test done (14-20 weeks) measures levels of: Alpha-fetoprotein (AFP) Human chorionic gonadotropin (hCG) Unconjugated estriol (UE3) Inhibin A', 'role': 'assistant'}]