This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T., Subject name: Radiology
[{'content': 'Double bubble appearance in plain X-ray is seen in : \nSelect and explain. \nA. Annular pancreas, B. Lobular pancreas, C. Ca pancreas, D. Pancreatitis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans: a (Annular pancreas) Ref: Bailey and Love, 24th ed, p. 1120Annular pancreas is due to failure of rotation of ventral pancreatic bud. On abdominal radiograph it shows "double -bubble"sign, due to interrupted gastro duodenal shadow produced by rigid ring of pancreatic tissue.Double bubble sign is also seen in:* Duodenal atresia* Duodenal stenosisRemember Single bubble sign- in pyloric stenosisDouble bubble sign- duodenal atresia, Ladd\'s band/malrotation, annular pancreasTriple bubble sign- is seen in jejunal atresiaGasless abdomen on X-ray* Acute pancreatitis* Annular pancreas* Bowel malrotation* Congenital hypertrophic pyloric stenosis* Congenital diaphragmatic hernia* Duodenal atresia* Mesenteric infarctionOther important signs* String of beads appearance-intestinal obstruction* Coffee bean sign-closed loop obstruction* Bird of prey sign in Barium enema-sigmoid volvulus* Chain of lakes in ERCP-chronic pancreatitis* Crow foot, Mercedes Benz sign-gall stones.', 'role': 'assistant'}]