This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General obstetrics, Subject name: Gynaecology & Obstetrics
[{'content': 'Increased levels of which of the following in amniotic fluid is an indicator of neural tube defect in the fetus : \nSelect and explain. \nA. Acetylcholinesterase, B. Butyrylcholinesterase, C. Pseudocholinesterase, D. Phosphatidyl esterase', 'role': 'user'}, {'content': "Answer: A \nExplanation: Acetylcholine esterase: (AChE) Amniotic fluid AChE level is elevated in most cases of open neural tube defects. It has got better diagnostic value than AFP. Reference: D C Dutta's Textbook of Obstetrics 7th edition page no 113", 'role': 'assistant'}]