Assertion `:-` The wall of atria release ANF in response to high B.P. and blood volume.
Reason `:-` ANF acts as a vasodilator and inhibits the release of renin to lower the blood pressure.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion .
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that the walls of the atria release Atrial Natriuretic Factor (ANF) in response to high blood pressure (BP) and increased blood volume.
- ANF is a hormone produced by the heart's atria when they are stretched due to increased blood volume.

2. **Understanding the Reason:**
- The reason explains the function of ANF, stating that it acts as a vasodilator and inhibits the release of renin, which helps to lower blood pressure.
- Vasodilation refers to the widening of blood vessels, which decreases resistance and lowers blood pressure.

3. **Linking Assertion and Reason:**
- The assertion is correct because ANF is indeed released when there is high blood pressure or increased blood volume.
- The reason is also correct as ANF promotes vasodilation and inhibits renin release, which contributes to lowering blood pressure.

4. **Conclusion:**
- Both the assertion and reason are true, and the reason correctly explains the assertion. Therefore, the answer is that both statements are true and the reason is the correct explanation for the assertion.