Assertion:Frog's tadpole has fish-like form, tail and gills
Reason: Tadpole stage is the recapitulation of the fish-like ancestor of frog in the latter's life history

Options

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

Answer

To analyze the assertion and reason provided in the question, we can break it down into a step-by-step solution.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Frog's tadpole has fish-like form, tail, and gills."
- This is true because tadpoles are aquatic and possess features such as a tail and gills, which are characteristic of fish.

2. **Understanding the Reason**:
- The reason states that "Tadpole stage is the recapitulation of the fish-like ancestor of the frog in the latter's life history."
- This refers to the concept of recapitulation, which suggests that the development of an organism (ontogeny) reflects the evolutionary history (phylogeny) of its species.

3. **Connecting Assertion and Reason**:
- The assertion and reason are connected through the concept of recapitulation. The tadpole's fish-like characteristics are seen as a reflection of the evolutionary history of frogs, which are believed to have evolved from fish-like ancestors.

4. **Biogenetic Law**:
- The biogenetic law, proposed by Ernst Haeckel, states that "ontogeny recapitulates phylogeny." This means that the development of an individual organism (ontogeny) mirrors the evolutionary development of that organism's species (phylogeny).
- In this context, the tadpole stage of frogs can be seen as a representation of their evolutionary past, where they exhibit features similar to those of fish.

5. **Conclusion**:
- Both the assertion and reason are correct. The tadpole does indeed have fish-like features, and these features reflect the evolutionary history of frogs as articulated by the biogenetic law. Therefore, the reason is a correct explanation for the assertion.

### Final Answer:
Both the assertion and the reason are true, and the reason correctly explains the assertion.

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