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: Pediatrics
What is the specific marker of Neural tube defects 
Select and explain. 
A. Estriol, B. Inhibin A, C. Acetylcholinesterase, D. Pregnancy - associated plasma protein A
C: Acetylcholinesterase
Answer: C: Acetylcholinesterase 
Explanation: Acetylcholinesterase is the specific biochemical marker for neural tube defects.