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
Thyroid ablation is done using which radioisotope of Iodine: March 2012 
Select and explain. 
A. I-123, B. I-125, C. I-131, D. I-135
C: I-131
Answer: C: I-131 
Explanation: 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