This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Abdominal Radiography, Subject name: Radiology
X-ray showing double-bubble sign in - 
Select and explain. 
A. Osophageal atresia, B. Pyloric stenosis, C. Duodenal atresia, D. Colonic atresia
C: Duodenal atresia
Answer: C: Duodenal atresia 
Explanation: Ans. is 'c' i.e. Duodenal atresia Condition in which double bubble appearance in seen -Duodenal atresia *Duodenal stenosis*Annular pancreas * Double bubble appearance or double stomach appearance is seen because of gross dilatation of the stomach and upper part of the duodenum with two-air fluid levels.Also knowSingle bubble appearance is seen in - Pyloric stenosis*