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: Medicine
[{'content': 'Abnormal a-fetoprotein is seen in \nSelect and explain. \nA. Trisomy 18, B. Twin pregnancy, C. Neural tube defect, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Answer is D (All of the above) All conditions mentioned in options are associated with abnormal Alpha fetoprotein levels. Open Neural tube defects and multiple gestations (twin pregnancy) are associated with elevated alpha protein levels Chromosomal trisomies (trisomy 18) show decreased alphaprotein levels.', 'role': 'assistant'}]