Assertion :- Human's brain having highly folded structure in gray matter as gyri & sulci.
Reason:- Gyri & sulci are also present in cerebellum.

Options

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

Answer

To analyze the given assertion and reason, we will break down the statements and evaluate their validity step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that the human brain has a highly folded structure in the gray matter, characterized by gyri and sulci.
- **Evaluation**: This statement is true. The human brain indeed has a highly folded structure, which increases the surface area for neurons and enhances cognitive functions.

2. **Understanding the Reason**:
- The reason states that gyri and sulci are also present in the cerebellum.
- **Evaluation**: This statement is also true. The cerebellum, like the cerebrum, has folds (gyri) and grooves (sulci) that increase its surface area.

3. **Analyzing the Relationship**:
- The assertion is true, and the reason is true, but we need to determine if the reason correctly explains the assertion.
- **Evaluation**: While both statements are true, the presence of gyri and sulci in the cerebellum does not explain why the human brain has a highly folded structure in the gray matter. The assertion pertains specifically to the cerebral cortex, while the reason refers to the cerebellum.

4. **Conclusion**:
- The correct relationship is that both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

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

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