State true or false.
Biological diversity is important for a stable environment.

Answer

**Step-by-Step Solution:**

1. **Understanding the Statement**: The statement we need to evaluate is "Biological diversity is important for a stable environment."

2. **Defining Biological Diversity**: Biological diversity, or biodiversity, refers to the variety of life forms in a particular habitat or ecosystem. This includes the interrelationship between different species of plants, animals, and microorganisms.

3. **Importance of Biodiversity**: Biodiversity contributes to a stable environment by ensuring that various species can coexist and support each other. A diverse ecosystem is more resilient to changes and disturbances, such as climate change or disease.

4. **Impact of Biodiversity on Abiotic Factors**: A rich biodiversity helps maintain the balance of abiotic factors (like sunlight, water, and soil quality) in the environment. For example, plants absorb CO2 and release oxygen, which is crucial for the survival of animals.

5. **Consequences of Reduced Biodiversity**: When biodiversity is reduced, such as through deforestation, the balance of the ecosystem is disrupted. This can lead to increased CO2 levels, rising temperatures, and other environmental issues, indicating that a stable environment is compromised.

6. **Conclusion**: Based on the understanding of biodiversity and its role in maintaining a stable environment, we can conclude that the statement is true.

**Final Answer**: True.

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