Assertion : A mixture is homogeneous in nature.
Reason : Mixtures show fixed composition.

Options

A. If both assertion and reason are true and reason is the correct explanation
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 both assertion and reason are false.

Explanation

To solve the assertion and reason question, we need to analyze both statements carefully.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "A mixture is homogeneous in nature."
- A homogeneous mixture is one where the components are uniformly distributed, and the composition is consistent throughout the mixture (e.g., saltwater).

2. **Understanding the Reason**:
- The reason states that "Mixtures show fixed composition."
- Fixed composition means that the ratio of the components in the mixture remains constant.

3. **Analyzing the Assertion**:
- Mixtures can be either homogeneous or heterogeneous.
- A homogeneous mixture has a uniform composition, while a heterogeneous mixture has a non-uniform composition (e.g., salad).
- Therefore, the assertion that a mixture is homogeneous in nature is **not always true**.

4. **Analyzing the Reason**:
- Mixtures do not have a fixed composition. The proportions of the components can vary.
- For example, you can have a mixture of sand and salt in different ratios, which means the composition is not fixed.
- Thus, the reason that mixtures show fixed composition is also **not true**.

5. **Conclusion**:
- Since both the assertion and the reason are false, we conclude that the correct answer is that both statements are incorrect.

### Final Answer:
Both the assertion and reason are false.

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