Biosphere is

Options

A. a component in the ecosystem
B. composed of the plants present on the soil
C. life in the outer space
D. composed of all living organisms present on earth which interact with the physical environment

Answer

To answer the question "Biosphere is," we will analyze the given options and determine the correct definition of the biosphere.

### Step-by-Step Solution:

1. **Understanding the Concept of Biosphere**:
- The biosphere refers to the global sum of all ecosystems. It is the zone of life on Earth, a closed system, and largely self-regulating. The biosphere is where living organisms interact with each other and their physical environment.

2. **Evaluating the Options**:
- **Option A**: "A component in the ecosystem" - This is partially true, as the biosphere includes ecosystems, but it does not fully capture what the biosphere is.
- **Option B**: "Composed of the plant present on the soil" - This is incorrect as it only refers to plants and does not encompass all living organisms.
- **Option C**: "Life in the outer space" - This is incorrect; the biosphere pertains to Earth and does not include extraterrestrial life.
- **Option D**: "Composed of all living organisms present on Earth which interact with the physical environment" - This is the most accurate definition of the biosphere, as it includes all living organisms and their interactions with the environment.

3. **Conclusion**:
- After evaluating all the options, the correct answer is **Option D**: "Composed of all living organisms present on Earth which interact with the physical environment."

### Final Answer:
The biosphere is composed of all living organisms present on Earth which interact with the physical environment.

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