Assertion: Habitat destruction is the main reason of loss of biodiversity.
Reason: This actually causes the increase in edge area and reduction in core area.

Options

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

Answer

### Step-by-Step Solution

1. **Understanding the Assertion**: The assertion states that "Habitat destruction is the main reason for the loss of biodiversity."
- Biodiversity refers to the variety of life forms in a specific area, including different species of plants, animals, and microorganisms. When habitats are destroyed, the organisms that depend on those habitats for survival are also affected, leading to a decline in biodiversity.

2. **Understanding the Reason**: The reason provided is that "This actually causes the increase in edge area and reduction in core area."
- Habitat destruction often leads to fragmentation of ecosystems. This fragmentation increases the edge area (the boundary where two different habitats meet) while reducing the core area (the interior part of a habitat that provides a safe space for organisms to live without disturbance).

3. **Connecting Assertion and Reason**:
- The assertion is correct because habitat destruction indeed leads to a loss of biodiversity. The reason is also correct because the increase in edge area and reduction in core area due to habitat destruction can lead to more stress on species, making them more vulnerable to extinction.
- The increase in edge area means that species that thrive in core areas are now exposed to dangers from outside their habitat, such as predators or human activities.

4. **Conclusion**: Both the assertion and the reason are correct, and the reason correctly explains why habitat destruction leads to loss of biodiversity. Therefore, the answer is that both statements are true and the reason is a correct explanation of the assertion.

### Final Answer
Both the assertion and the reason are correct, and the reason correctly explains the assertion.