Reabsorption of `Na^(+)` from the distal part of the tubule is controlled by which hormone ?

Options

A. Rennin
B. Thyroxin
C. Aldosterone
D. Testosterone

Answer

To solve the question regarding which hormone controls the reabsorption of Na⁺ from the distal part of the tubule, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the hormone responsible for the reabsorption of sodium ions (Na⁺) in the distal convoluted tubule (DCT) of the nephron.

2. **Identifying Relevant Hormones**: We need to consider the hormones that are known to influence sodium reabsorption in the kidneys. The primary hormones involved include:
- Renin
- Aldosterone
- Thyroxine
- Testosterone

3. **Analyzing Each Hormone**:
- **Renin**: This is an enzyme that plays a role in regulating blood pressure but is not directly responsible for sodium reabsorption.
- **Thyroxine**: This hormone is primarily involved in metabolism and growth, not in sodium reabsorption.
- **Aldosterone**: This hormone is produced by the adrenal glands and is crucial for sodium reabsorption in the kidneys. It acts on the distal convoluted tubule and collecting duct to increase sodium reabsorption and potassium excretion.
- **Testosterone**: This is a sex hormone and does not have a direct role in sodium reabsorption.

4. **Conclusion**: Based on the analysis, the hormone that directly controls the reabsorption of Na⁺ from the distal part of the tubule is **Aldosterone**.

### Final Answer:
The hormone that controls the reabsorption of Na⁺ from the distal part of the tubule is **Aldosterone**.