21. 下列諸症狀中,何者與甲狀腺機能不足(hypothyroidism)無關? (A)胡蘿蔔素血症(β-carotenemia) (B)呆小症(cretinism) (C)格雷夫氏症 (Graves' disease) (D)粘液水腫(myxedema)