Assertion : Lung fish is connective link between fishes and amphibia.
Reason : Lung fishes show characters of both fishes and amphibia.

Options

A. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion, then mark (1)
B. If both Assertion and Reason are true ,but the Reason is not the correct explanation of the Assertion, then mark (2).
C. If Assertion is true, but Reason is false , then mark (3)
D. If both Assertion and Reason are false. , then mark (4)

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Lung fish is a connective link between fishes and amphibians." This means that lung fish possess traits that are characteristic of both groups.

2. **Understanding the Reason**: The reason provided is that "Lung fishes show characters of both fishes and amphibians." This implies that lung fish have features that are typical of both fishes (like gills) and amphibians (like lungs).

3. **Identifying Characteristics**:
- **Fish Characteristics**: Lung fish have a streamlined body and possess gills, which are typical features of fish.
- **Amphibian Characteristics**: Lung fish also possess lungs, which allow them to breathe air, a characteristic feature of amphibians.

4. **Connecting the Assertion and Reason**: Since lung fish exhibit both fish-like and amphibian-like characteristics, they serve as a connecting link between the two groups. Therefore, the reason provided supports the assertion.

5. **Conclusion**: Both the assertion and reason are true, and the reason correctly explains the assertion. Thus, the answer to the question is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

**Final Answer**: 1 (Both assertion and reason are true, and the reason is the correct explanation of the assertion.)

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