Which of these descriptions applies to the iodide pump

A)a mechanism whereby target cells extract iodine-containing thyroid hormone from the blood
B)an active transport mechanism that concentrates iodine in the thyroid
C)a mechanism whereby T₃ and T₄ are released from thyroglobulin and pumped into the circulation
D)a protein-binding process whereby T₃ and T₄ are pumped throughout the body bound to plasma proteins