- A A long-term deficiency of circulating insulin hormone normally secreted by the pancreas itself in routine practice
- B Iodine deficiency leading to low thyroid hormone production and compensatory TSH-driven thyroid enlargement
- C Excess secretion of cortisol hormone from the adrenal cortex under prolonged chronic stress overall in most cases
- D Excess secretion of growth hormone released from the anterior pituitary gland over time under typical conditions
Correct answer: B. Iodine deficiency leading to low thyroid hormone production and compensatory TSH-driven thyroid enlargement
Explanation: Goitre is enlargement of the thyroid gland. Most common cause: iodine deficiency (needed for thyroid hormone T3/T4 synthesis). Low T3/T4 → high TSH (from pituitary) → TSH stimulates thyroid growth → goitre. Endemic in inland areas with iodine-poor soil/water.
Concept context
Pathogens, infectious diseases, non-infectious diseases, drugs, cancer, and public health. High NEET importance.