A: India falls under oriental realm out of other biogeographical realms.
R: World is divided in six biogeographical realms.

Options

A. If both Assertion `&` Reason are true and the reason is the correct explanation of the assertion. Then mark (1)
B. If both Assertion `&` Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are falses statements, then mark (4)

Answer

To solve the assertion and reason question, we can break it down into clear steps:

### Step-by-Step Solution:

1. **Understand the Assertion (A)**:
- The assertion states that "India falls under the Oriental realm out of other biogeographical realms."
- This statement is true. India is indeed classified under the Oriental realm according to Alfred Russel Wallace's biogeographical classification.

2. **Understand the Reason (R)**:
- The reason states that "The world is divided into six biogeographical realms."
- This statement is also true. Alfred Russel Wallace identified six major biogeographical realms based on the distribution of organisms.

3. **Evaluate the Relationship**:
- While both statements are true, we need to determine if the reason correctly explains the assertion.
- The assertion specifically mentions the classification of India, while the reason discusses the overall division of the world into six realms. Therefore, the reason does not provide a direct explanation for why India is classified under the Oriental realm.

4. **Conclusion**:
- Both the assertion and reason are true, but the reason does not correctly explain the assertion.
- Thus, the correct option is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

### Final Answer:
Both the assertion (A) and reason (R) are true, but the reason (R) is not the correct explanation of the assertion (A).

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