Assertion : The duct - billed Platypus and the spiny anteater, both are egg - laying animals yet are grouped under mammals.
Reason : Both of them have seven cervical vertbrae and mammary glands without teats.
(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.

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

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

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that the duck-billed platypus and the spiny anteater are both egg-laying animals and are classified as mammals.
- This is true. Both the duck-billed platypus and the spiny anteater (also known as the echidna) are indeed mammals that lay eggs, which is a characteristic of a specific group of mammals called monotremes.

2. **Understanding the Reason**:
- The reason states that both animals have seven cervical vertebrae and mammary glands without teats.
- This statement is also true. Monotremes, including the platypus and echidna, do have seven cervical vertebrae, and they possess mammary glands, although they do not have teats like most other mammals.

3. **Evaluating the Relationship**:
- The assertion is true, and the reason is also true. However, the reason does not directly explain why the assertion is true. The classification of these animals as mammals is based on their overall characteristics (like having mammary glands) rather than just the presence of cervical vertebrae or the absence of teats.

4. **Conclusion**:
- Since both the assertion and the reason are true, but the reason does not explain the assertion, the correct answer is (b): If both Assertion and Reason are true, but the Reason is not the correct explanation of the Assertion.

### Final Answer:
(b) If both Assertion and Reason are true, but the Reason is not the correct explanation of the Assertion.

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