Assertion : Density of an incompressible liquid is constant.
Reason : An ideal fluid is incompressible.

Options

A. If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
B. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If Assertion is false but Reason is true.

Explanation

To solve the question, we need to analyze the assertion and the reason provided:

**Assertion:** The density of an incompressible liquid is constant.
**Reason:** An ideal fluid is incompressible.

### Step-by-Step Solution:

1. **Understanding the Assertion:**
- The assertion states that the density of an incompressible liquid is constant.
- By definition, an incompressible fluid is one whose density does not change when pressure is applied. This means that the volume does not change under pressure, leading to a constant density.

2. **Understanding the Reason:**
- The reason states that an ideal fluid is incompressible.
- An ideal fluid is a theoretical concept in fluid mechanics that assumes no viscosity and incompressibility. This means that, for an ideal fluid, the density remains constant regardless of pressure changes.

3. **Evaluating the Relationship:**
- Both the assertion and the reason are true statements. The assertion is a general statement about incompressible liquids, while the reason specifically refers to ideal fluids.
- However, the assertion applies to all incompressible liquids, not just ideal fluids. Therefore, while the reason is true, it does not serve as a direct explanation for the assertion.

4. **Conclusion:**
- Both the assertion and the reason are correct, but the reason does not correctly explain the assertion.
- Thus, the correct choice is: "Both assertion and reason are true, but the reason is not a correct explanation for the assertion."

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

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