A biosphere is composed of

Options

A. Living organisms
B. Living organisms+lithosphere
C. Living organisms+lithosphere+hydrosphere
D. Living organisms+lithosphere+atmosphere hydrosphere

Answer

To answer the question "A biosphere is composed of," we can break down the components of the biosphere step by step.

### Step-by-Step Solution:

1. **Understanding the Biosphere**:
- The biosphere is defined as the global sum of all ecosystems. It is the zone of life on Earth, a closed system that includes all living organisms and their physical environment.

2. **Components of the Biosphere**:
- The biosphere consists of both biotic (living) and abiotic (non-living) components.
- Biotic components include all living organisms such as plants, animals, fungi, and microorganisms.
- Abiotic components include the physical environment, which can be divided into three main spheres:
- **Atmosphere**: The layer of gases surrounding the Earth.
- **Hydrosphere**: All the water bodies on Earth, including oceans, rivers, lakes, and groundwater.
- **Lithosphere**: The solid outer part of the Earth, including soil and rocks.

3. **Combining the Components**:
- Therefore, the biosphere is composed of:
- Living organisms (biotic factors)
- Atmosphere (abiotic factor)
- Hydrosphere (abiotic factor)
- Lithosphere (abiotic factor)

4. **Final Conclusion**:
- The complete composition of the biosphere can be summarized as:
- Living organisms + Atmosphere + Hydrosphere + Lithosphere.

### Answer:
The biosphere is composed of living organisms, atmosphere, hydrosphere, and lithosphere.

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