<prompt> Which of the following is the derivative of ultimobranchial body?ThyroidParafollicular C cellsCapsule of thyroid2nd branchial pouch  <response>: Ans. B Parafollicular C cellsRef: Grays Anatomy E-book. P 61ENDODERMAL POUCHES 1st pouch: Dorsal part forms tub tympanic recess which forms the middle ear cavity and eustachian tube. 2nd pouch: Joins with ventral part of 1st pouch to form palatine tonsil. Also forms parts of middle ear. 3rd pouch: Dorsal part forms the inferior parathyroid gland and ventral forms thymus. 4th pouch: Dorsal part forms the superior parathyroid gland. Ventral part forms the ultimobranchial body which forms the parafollicular C-cells of thyroid. 