Assertion (A): Tadpole stage of frog has both gills and fins.
Reason (R): Gills help in breathing and fins help in swimming.

Options

A. A is correct and R is the correct explanation of A.
B. A is correct and R is not the correct explanation of B.
C. A is correct and R is wrong.
D. A is wrong and R is correct.

Answer

To analyze the assertion and reason provided in the question, we can follow these steps:

### Step 1: Understand the Assertion
The assertion states that "the tadpole stage of frog has both gills and fins."
- **Explanation**: The tadpole is the larval stage of frogs, and during this stage, they possess gills for respiration and fins for swimming.

### Step 2: Understand the Reason
The reason states that "gills help in breathing and fins help in swimming."
- **Explanation**: Gills are specialized organs that allow aquatic animals like tadpoles to extract oxygen from water, while fins are appendages that aid in swimming and movement in water.

### Step 3: Evaluate the Relationship
Now, we need to determine if the reason correctly explains the assertion.
- **Analysis**: Since gills are indeed used for breathing in water and fins are used for swimming, the reason supports the assertion.

### Step 4: Conclusion
Both the assertion and the reason are correct, and the reason provides a correct explanation for the assertion. Therefore, the correct option is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer:
Assertion (A) is correct, and Reason (R) is correct and provides the correct explanation for Assertion (A).

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