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': 'Which one of the following imaging techniques gives maximum radiation exposure to the patient? \nSelect and explain. \nA. Chest X-ray, B. MRI, C. CT scan, D. Bone scan', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Radiation exposure (in decreasing order)\nCT scan > Bone scan > X-ray\nMRI & USG has no radiation risk', 'role': 'assistant'}]