<prompt> Most specific marker of neural tube defects is:Alpha fetoproteinPseudocholinesteraseAcetylcholinesteraseInhibin  <response>: Ans. is c i.e. Acetylcholinesterase NTD is suspected if the maternal serum AFP is elevated, and if the ultrasonographic examination is nondiagnostic, then amniotic fluid AFP levels are measured. An elevated amniotic fluid AFP level prompts assay of the same sample for acetylcholinesterase. The presence of this enzyme 100 confirms that exposed neural tissue or another open fetal defect is present. AFP is not specific is elevated in many conditions. 