<prompt> Which of the following feature on second trimester ultrasound is not a marker of Downs syndrome:Single umbilical aeryChoroids plexus cystPolycystic kidneysDuodenal atresia  <response>: USG findings in downs syndrome are Intrauterine growth restriction Mild cerebral ventriculomegaly Choroid plexus cysts Increased nuchal fold thickness Cystic hygromas Diaphragmatic hernia Echogenic intracardiac foci Congenital hea defects Increased intestinal echogenicity Duodenal atresia double-bubble sign Renal pelvis dilation Shoened humerus and femur Increased iliac wing angle Incurving clinodactyly and hypoplasia of the fifth finger Increased space between first and second toes: sandal gap Two-vessel umbilical cordsingle Umblical aery 