Most important feature to diagnose fetal aneuploidy:: (A) Absent nasal bone, (B) Nuchal translucency, (C) Increase in frontomaxillary angle, (D) Reversal of ductus venosus flow
Answer is B. B i.e. Nuchal translucencyRef: Current Progress in Obstetrics and Gynecology; John Stud, Volume 1, page 17Explanation:Ultrasound Markers of Fetal Aneuploidy:Nuchal translucency is the single most powerful tool. More than 3 mm needs evaluation.Absence of nasal bone.Absence or reversal of flow in the ductus venosus on Doppler.Tricuspid regurgitation.Increase in frontomaxillary angle more than 85 deg.