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: Radiology
[{'content': 'Double bubble sign seen in: \nSelect and explain. \nA. Duodenal atresia, B. Ileal atresia, C. Pyloric stenosis, D. Pancreatic divisum', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. Duodenal atresia', 'role': 'assistant'}]