Answer: C. Producing too much of the thyroid horomone.
Explanation: The definition of hyperthyroidism is the condition that occurs due to excessive production of thyroid hormones by the thyroid gland.
If you further break the answer down you can deduct that the prefix 'hyper' in Greek is “over while 'hypo' is less. So Hyper=more and hypo= less.
Aswells as the meaning of Hypothyroidism means that the thyroid gland can't make enough thyroid hormone to make the body function normally.
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