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: Surgery
[{'content': 'Double bubble sign seen in : \nSelect and explain. \nA. Duodenal atresia, B. Duodenal stenosis, C. Volvulus, D. All', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'a', 'b' & 'c' i.e. Duodenal atresia, Duodenal stenosis and Volvulus", 'role': 'assistant'}]