C

The normal TSH range is 0.28-3.89 µIu/mL. Levothyroxine is a thyroid replacement hormone used to treat hypothyroidism. Patients on levothyroxine should have their TSH levels checked at least once per year. (Resp. Ex. 5 at 50; Angel testimony - Tr. at 397; Friedman testimony - Tr. at 645-646.) ................
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