Which of the following is the most likely explanation for hypothyroidism in a patient whose iodine level is normal?
A) greater production of T₃ than of T₄
B) hyposecretion of TSH
C) hypersecretion of MSH
D) a decrease in the thyroid secretion of calcitonin

Question

Quizplus · Accepted Answer

Hypothyroidism is typically caused by a decrease in thyroid hormone production, which can be due to a problem with the thyroid gland itself (primary hypothyroidism) or due to inadequate stimulation by thyroid stimulating hormone (TSH) from the pituitary gland (secondary hypothyroidism). Since iodine is necessary for the production of thyroid hormones, a lack of iodine can cause hypothyroidism. However, if iodine levels are normal, the most likely explanation for hypothyroidism is a problem with TSH secretion, leading to decreased thyroid hormone production. The other options (A, C, and D) are not commonly associated with hypothyroidism.

Which of the Following Is the Most Likely Explanation for Hypothyroidism