Answer:
The correct answer is option C. the anterior pituitary gland decreased its production of TSH.
Explanation:
The negative feedback loop is the mechanism in that a hormone inhibits or its product inhibits or decreases its own secretion in the blood level with an increase or decrease of its level.
The negative feedback loop of the levels of the thyroid hormones which are T3 and T4 in blood level send signals the anterior part of the pituitary gland that inhibits or decreases the production of TSH and TRH.
Thus, the correct answer is option C. the anterior pituitary gland decreased its production of TSH.