<prompt> Derivative of third pharyngeal pouch is:ThymusInferior parathyroid glandBoth of the aboveNone of the above  <response>: In the fifth week, epithelium of the dorsal region of the third pouch differentiates into the inferior parathyroid gland, while the ventral region forms the thymus. Ref: Langmans embryology 11th edition Chapter 16. 