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': 'Thyroid ablation is done using which radioisotope of Iodine: March 2012 \nSelect and explain. \nA. I-123, B. I-125, C. I-131, D. I-135', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans: C i.e. I-131 Iodine radioisotopes and uses I-123 is the agent of choice for radioactive iodine uptake/ RAIU I-131 is used as NaI in diagnosis and treatment of thyroid diseases', 'role': 'assistant'}]