is a pituitary hormone that has no role in reproductive physiology.

Correct Answer: D

Rationale: Vasopressin regulates water balance, not reproduction.

Correct Answer: A

Rationale: Albumin has the largest capacity to bind thyroxine due to its high plasma concentration, though TBG has higher affinity. Transferrin and ferritin are involved in iron transport/storage, not thyroxine.

Correct Answer: D

Rationale: Exercise stimulates glucagon secretion to mobilize glucose. Somatostatin, glucose, and insulin inhibit it, while ketones have a lesser direct effect.

Correct Answer: B

Rationale: Aldosterone has minor glucocorticoid action but primarily regulates Na^+/K^+ via nuclear receptors, not G-proteins. It responds to hyperkalemia, causes acidic urine, and is protein-bound.

Correct Answer: A

Rationale: Chromium enhances insulin action; its deficiency leads to insulin resistance and glucose intolerance.