Carbohydrate metabolism is governed by :

Options

A. Thyroxine
B. Insulin
C. Glucocorticoids
D. All

Answer

**Step-by-Step Solution:**

1. **Identify the Key Hormones Involved in Carbohydrate Metabolism:**
- The primary hormones that govern carbohydrate metabolism include thyroxine (T4), insulin, and glucocorticoids (like cortisol).

2. **Understand the Role of Thyroxine (T4):**
- Thyroxine is secreted by the thyroid gland and is crucial for regulating the basal metabolic rate. It influences the metabolism of carbohydrates, proteins, and fats, thereby playing a significant role in carbohydrate metabolism.

3. **Examine the Function of Insulin:**
- Insulin is produced by the pancreas and is primarily responsible for lowering blood glucose levels. It facilitates the uptake of glucose by cells, thus directly impacting carbohydrate metabolism.

4. **Analyze the Impact of Glucocorticoids:**
- Glucocorticoids, such as cortisol, are secreted by the adrenal glands. They have the opposite effect of insulin as they increase blood glucose levels, thereby influencing carbohydrate metabolism.

5. **Conclusion:**
- All three hormones (thyroxine, insulin, and glucocorticoids) play significant roles in regulating carbohydrate metabolism. Therefore, the correct answer to the question is that carbohydrate metabolism is governed by these hormones.

**Final Answer:**
Carbohydrate metabolism is governed by thyroxine, insulin, and glucocorticoids.

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