Parafollicular cells (C-cells) in the thyroid are derived from: (A) Neural crest, (B) Ultimobranchial body, (C) Median bud of pharynx, (D) Pharyngeal pouch
Answer is B. Cells of the ultimobranchial body give rise to the parafollicular, or C cells of the thyroid gland. These cells secrete calcitonin, a hormone involved in regulation of the calcium level in the bloodRef: Langman&;s Medical embryology; 12th edition; Chapter 17; Head and Neck