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
Which one of the following biochemical parameters is the most sensitive to detect open spina bifida ? 
Select and explain. 
A. Maternal serum alpha fetoprotein, B. Amniotic fluid alpha fetoprotein, C. Amniotic fluid acetyl cholinesterase, D. Amniotic fluid glucohexaminase
C: Amniotic fluid acetyl cholinesterase
Answer: C: Amniotic fluid acetyl cholinesterase 
Explanation: None