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
[{'content': 'Barium swallow is used for- \nSelect and explain. \nA. Colon, B. Esophagus, C. Duodenum, D. Jejunum', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., EsophagusBarium investigationUsed to visualizeBarium swallowMainly for esophagusBarium mealEsophagus, stomach, duodenumBarium follow throughSmall intestine (jejunum and ileum)Barium enemaLarge intestine (colon & rectum)", 'role': 'assistant'}]