Derivative of third pharyngeal pouch is:: (A) Thymus, (B) Inferior parathyroid gland, (C) Both of the above, (D) None of the above
Answer is C. 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: Langman's embryology 11th edition Chapter 16.