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': '"Time of Flight" technique is used in \nSelect and explain. \nA. HRCT, B. MR imaging, C. Spiral CT, D. Conventional radiography', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Time of Flight is used in MR imaging.', 'role': 'assistant'}]