Assertion : Birds have metanephric kidney and no urinary bladder.
Reason : South American ostrich has urinary bladder .

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Birds have metanephric kidney and no urinary bladder." This is true. Birds possess metanephric kidneys, which are efficient for excretion, and they typically do not have a urinary bladder or have it in a reduced form.

2. **Understanding the Reason**: The reason provided is that "South American ostrich has urinary bladder." This is also true. The ostrich is an exception among birds as it does possess a urinary bladder for storing urine.

3. **Evaluating the Relationship**: While both the assertion and reason are true, the reason does not serve as a correct explanation for the assertion. The assertion is a general statement about birds, while the reason is an exception regarding the ostrich.

4. **Conclusion**: Since both statements are true but the reason does not explain the assertion, the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

5. **Final Answer**: The correct option is B: Both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.

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