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': 'Isotope used for RAIU is ? \nSelect and explain. \nA. 1-123, B. 1-137, C. 1-125, D. None', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is'a'i.e., I-123Radio-active iodine uptake (RAIU) test is used to measure thyroid function.Usual isotope of radioiodine used b I-123.", 'role': 'assistant'}]