Which hormone is produced by the thyroid gland?

Choice A rationale Cortisol is a glucocorticoid hormone produced by the adrenal cortex. It is involved in the body's stress response, metabolism, and immune function, but is not produced by the thyroid gland, which is primarily focused on metabolic regulation. Choice B rationale Thyroxine, also known as T4, is the main hormone produced by the thyroid gland. It is a key regulator of metabolism, growth, and development. The thyroid also produces a smaller amount of triiodothyronine (T3), which is more potent than T4. Choice C rationale Insulin is a hormone produced by the beta cells of the pancreas. Its primary role is to regulate blood glucose levels by promoting the uptake of glucose into cells for energy or storage. It is not associated with thyroid function. Choice D rationale Adrenaline, or epinephrine, is a hormone produced by the adrenal medulla. It is a crucial part of the "fight or flight" response, increasing heart rate, blood pressure, and glucose release from stores, and is unrelated to the thyroid gland.