This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Obstetrics, Subject name: Gynaecology & Obstetrics
Normally, Nuchal Translucency should be : 
Select and explain. 
A. More than 10mm, B. Less than 6mm, C. Less than 3 mm, D. More than 5 mm
C: Less than 3 mm
Answer: C: Less than 3 mm 
Explanation: Fetal nuchal translucency is the maximum thickness of the subcutaneous translucent area between the skin and soft tissue that overlies the fetal spine in the sagittal plane. It is measured between 11- 14 weeks of gestation. Up to 3 mm is considered normal. NT > 3 mm is a marker for aneuploidys. like trisomy 21.