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': 'Dye used for myelography \nSelect and explain. \nA. Conray 320, B. Myodil, C. Dianosil, D. Iopaoic acid', 'role': 'user'}, {'content': 'Answer: B \nExplanation: contrast agents used for myelography are : Iohexol Iopamidol Metrizamide Myodil', 'role': 'assistant'}]