Assertion: PTH is a hypercalcemic hormone.
Reason: Thymus degenerates in old individuals.

Options

A. Assertion and reason are both true
B. Assertion and reason are both false
C. assertion is true but the reason is false
D. assertion is false but the reason is true

Explanation

To analyze the given assertion and reason, we will break down each component step by step.

### Step 1: Understand the Assertion
The assertion states that "PTH is a hypercalcemic hormone."

- **Explanation**: PTH stands for parathyroid hormone, which is produced by the parathyroid glands. Its primary function is to regulate calcium levels in the blood. PTH increases the concentration of calcium in the blood (hypercalcemia) by promoting the release of calcium from bones, increasing calcium reabsorption in the kidneys, and enhancing calcium absorption from the intestine.

### Step 2: Understand the Reason
The reason states that "Thymus degenerates in old individuals."

- **Explanation**: The thymus is an organ that plays a crucial role in the immune system, particularly during childhood. It produces hormones like thymosin that are essential for the development of T-cells, which are vital for the immune response. As individuals age, the thymus undergoes atrophy, meaning it shrinks and loses its function, which is why it is less prominent in older individuals compared to children.

### Step 3: Evaluate the Relationship Between Assertion and Reason
Now we need to evaluate if the reason provided supports the assertion.

- **Analysis**: While both statements are true, they are independent of each other. The hypercalcemic effect of PTH does not relate to the degeneration of the thymus in older individuals. Therefore, while both the assertion and reason are correct, the reason does not explain or support the assertion.

### Conclusion
Both the assertion and reason are true, but the reason does not support the assertion. Thus, the correct answer is that both statements are true, but the reason is not the correct explanation for the assertion.

### Final Answer
- Both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

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