Zona glomerulosa or glomerular area of adrenal cortex is involved in 

Options

A. Water and electrolyte balance
B. Carbohydrate metabolism
C. Steroid and hormone secretion
D. Blood pressure.

Answer

### Step-by-Step Solution:

1. **Identify the Location**: The zona glomerulosa is the outermost layer of the adrenal cortex, which is situated on top of the kidneys.

2. **Function of Zona Glomerulosa**: This layer is primarily responsible for the secretion of mineralocorticoids, the most notable of which is aldosterone.

3. **Role of Aldosterone**: Aldosterone plays a crucial role in regulating water and electrolyte balance in the body. It promotes the reabsorption of sodium and water in the kidneys, which helps to maintain blood volume and pressure.

4. **Potassium Excretion**: In addition to sodium and water reabsorption, aldosterone also facilitates the excretion of potassium, which is essential for maintaining electrolyte balance.

5. **Involvement in RAAS**: The zona glomerulosa is also involved in the Renin-Angiotensin-Aldosterone System (RAAS), which is a hormone system that regulates blood pressure and fluid balance.

6. **Conclusion**: Therefore, the primary involvement of the zona glomerulosa is in maintaining water and electrolyte balance, along with its role in regulating blood pressure through aldosterone secretion.

### Final Answer:
The zona glomerulosa or glomerular area of the adrenal cortex is involved in maintaining water and electrolyte balance.

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