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': 'Radiation exposure occurs in all except: \nSelect and explain. \nA. CT scan, B. Plain X-ray, C. Fluoroscopy, D. MRI', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. MRI', 'role': 'assistant'}]