Assertion : Cold-blooded animals have no subcutaneous fat layer.
Reason: Cold-blooded animals use their fat for metabolic processes during hibernation.

Options

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

Answer

To solve the question regarding the assertion and reason provided, we will analyze both statements step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Cold-blooded animals have no subcutaneous fat layer."
- Cold-blooded animals, also known as ectotherms, are organisms that cannot regulate their body temperature internally. Instead, their body temperature fluctuates with the environment.
- Generally, many cold-blooded animals do not have a significant layer of subcutaneous fat because they rely on environmental conditions for thermoregulation.

2. **Understanding the Reason**:
- The reason states that "Cold-blooded animals use their fat for metabolic processes during hibernation."
- Hibernation is a state of reduced metabolic activity that some cold-blooded animals enter during adverse environmental conditions, such as winter.
- During hibernation, these animals may utilize stored energy, which can include fat, to sustain their metabolic needs when food is scarce.

3. **Evaluating the Relationship**:
- The assertion claims that cold-blooded animals lack a subcutaneous fat layer, which is generally true for many of these animals.
- The reason explains that fat is used for metabolic processes during hibernation, which is also true.
- However, the reason does not directly explain the assertion. Just because cold-blooded animals use fat during hibernation does not mean they do not have a subcutaneous fat layer; rather, it indicates their metabolic adaptations.

4. **Conclusion**:
- Both the assertion and the reason are true, but the reason is not a correct explanation of the assertion.
- Therefore, the correct option is: "Both assertion and reason are true, but reason is not a correct explanation of assertion."

### Final Answer:
Both assertion and reason are true, but reason is not a correct explanation of assertion.

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