This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
A neonate with Down syndrome is having bilious vomiting 
Select and explain. 
A. Duodenal atresia, B. Congenital hypertrophic pyloric stenosis, C. Ileal atresia, D. Anorectal malformation
A: Duodenal atresia
Answer: A: Duodenal atresia 
Explanation: Ans. (a) Duodenal atresia Ref - The image shows the presence of double bubble appearance suggestive of diagnosis of duodenal atresia. About 8% of children with Down syndrome are born with duodenal atresia which presents with bilious vomiting.