Answer:
D. body cell metabolism.
Step-by-step explanation:
The role of the thyroid gland is to gain iodine, detected in many foods, and transform it in thyroid hormones: thyroxine (T4) and triiodothyronine (T3). Thyroid cells are the unique cells in the body which can consume iodine. These cells merge iodine and the amino acid tyrosine to produce T3 and T4. T3 and T4 are then discharged into the bloodstream and are carried completely that body where they manage metabolism (regeneration of oxygen and calories to power).