All the habitable zones on the Earth constitute

Options

A. Biosphere
B. Terrestrial biome
C. Aquatic biome
D. Community

Answer

To answer the question "All the habitable zones on the Earth constitute," we need to analyze the provided options and understand the definitions of each term.

### Step-by-Step Solution:

1. **Understanding the Question**: The question is asking about the collective areas on Earth where life can exist, commonly referred to as habitable zones.

2. **Analyzing the Options**:
- **Biosphere**: This term refers to the global sum of all ecosystems. It includes all living organisms and their relationships with the environment. The biosphere encompasses all habitats on Earth, including terrestrial and aquatic environments.
- **Terrestrial Biome**: This refers specifically to land-based ecosystems. While it is a part of the biosphere, it does not encompass aquatic habitats.
- **Aquatic Biome**: This refers specifically to water-based ecosystems. Like terrestrial biomes, it is part of the biosphere but does not include land habitats.
- **Community**: This term refers to a group of interacting species living in a particular area. It is a smaller scale than the biosphere and does not encompass all habitats.

3. **Identifying the Correct Answer**: Since the question asks for all habitable zones, the most comprehensive term that includes all types of habitats (both terrestrial and aquatic) is the **Biosphere**.

4. **Conclusion**: Therefore, the correct answer to the question is **Biosphere**.

### Final Answer:
All the habitable zones on the Earth constitute the **Biosphere**.

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