Problem: Nurse John is caring for a patient presenting with fatigue, weight gain, and cold intolerance, and suspects hypothyroidism. What is the primary pathophysiological mechanism of hypothyroidism, and which laboratory test result is most indicative of primary hypothyroidism? Need Assignment Help?
A. O Increased thyroid-stimulating hormone (TSH) levels; Low TSH and high T4 B. O Insufficient production of thyroid hormones; High TSH and low T4 C. 0 Decreased sensitivity to thyroid hormones; High TSH and high T4 D. O Excess production of thyroid hormones; Low TSH and low T4