C

Low serum TSH (initial test of choice), elevated T4, elevated T3 (if TSH and T4 are inconclusive) Radioactive T3 uptake (testing TBG) - - if TBG is fully bound by T4, T3 will bind to resin administered. This test helps to differentiate between elevations in thyroid hormones due to increased TBG from true hyperthyroidism. hyperthyroidism = ( T4 ................
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