<prompt> Commonest cause of intestinal obstruction in Down syndrome is:Colonic atresiaIntestinal atresiaDuodenal atresiaEsophageal atresia  <response>: c. Duodenal atresiaRef: Nelsons 20e p 610-615, Ghai 8e p 637-639Most common cause of Intestinal obstruction in Downs syndrome is duodenal atresia. 