This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fundamentals in Radiology, Subject name: Radiology
[{'content': 'Contrast material used in the diagnosis of esophageal atresia is - \nSelect and explain. \nA. Gastrograffin, B. Conray 420, C. Dianosil, D. Myodii', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Dianosil is the contrast agent used for Esophageal atresis, tracheo esophageal fistula and bronchoscopy.', 'role': 'assistant'}]