32 下列有關 Thyroid Hormones 之敘述，何者錯誤？
(A) T 3 之半衰期較 T 4 短
(B) T 3 與受器之親合力比 T 4 低 10 倍
(C)與 Phenytoin 併用時，其代謝將變快
(D)於甲狀腺機能亢進病人，其半衰期將變短

T3活性應大於T4，非低於

The thyroid hormones, triiodothyronine(T3) and its prohormone, thyroxine(T4), are tyrosine-based hormones produced by the thyroid gland that are primarily responsible for regulation of metabolism. Iodine is necessary for the production of T3 and T4. A deficiency of iodine leads to decreased production of T3 and T4, enlarges the thyroid tissue and will cause the disease known as goitre. The major form of thyroid hormone in the blood is thyroxine(T4), which has a "longer" half-life than T3. The ratio of T4 to T3 released into the blood is roughly 20 to 1. T4 is converted to the active T3 within cells by deiodinases. These are further processed by decarboxylation and deiodination to produce iodothyronamine and thyronamine. All three isoforms of the deiodinases are selenium-containing enzymes, thus dietary selenium is essential for T3 production. 

T4 : 半衰期長、總量多、蛋白質結合量多。

其他都輸

半衰期：T₄(7天）>T₃(1天）

與受體親和力：T₃高於T₄10倍