This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thyroid Gland, Subject name: Surgery
[{'content': 'In treatment of papillary carcinomas thyroid, radioiodine destroys the neoplastic cells predominantly by: \nSelect and explain. \nA. X-rays, B. Beta rays, C. Gamma rays, D. Alpha particles', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) Beta raysRef: Schwartz 10th edition, Page 1546* I-131 emits Beta radiation and penetrates the thyroid tissue up to 0.5mm without damaging the adjacent structures like parathyroid.', 'role': 'assistant'}]