<prompt> In treatment of papillary carcinomas thyroid, radioiodine destroys the neoplastic cells predominantly by:X-raysBeta raysGamma raysAlpha particles  <response>: 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. 