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': 'I/V contrast is not used in – \nSelect and explain. \nA. HRCT, B. MRI, C. IVP, D. Myelography', 'role': 'user'}, {'content': 'Answer: D \nExplanation: IV contrast agent is given in :-\n\n\nX-ray based investigation (Radiocontrast agent) :- Radiography (simple x-ray), CT-Scan.\nMRI (MR contrast agents).\nUltrasound (USG contrast agents).\n\n\nIVP (intravenous pyelography) as the name suggests, the contrast agent is given intravenously.\nIn myelography, the contrast agent is injected into subarachnoid space.', 'role': 'assistant'}]