The part of earth in which living organisms exist ( or which supports life ) is called :

Options

A. lithosphere
B. globe
C. hydrosphere
D. biosphere

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the part of the Earth that supports life or where living organisms exist.

2. **Identifying the Options**: The options provided are:
- A) Lithosphere
- B) Globe
- C) Hydrosphere
- D) Biosphere

3. **Defining Each Option**:
- **Lithosphere**: This refers to the outer rocky part of the Earth, which includes the crust and the upper mantle. It is not specifically where life exists.
- **Globe**: This term generally refers to the Earth as a whole and does not specifically denote a part that supports life.
- **Hydrosphere**: This encompasses all the water bodies on Earth, including oceans, rivers, and lakes. While water is essential for life, it is not the only component that supports living organisms.
- **Biosphere**: This is the correct term that refers to the part of Earth where life exists. It includes all ecosystems and living organisms, along with the non-living components that support them.

4. **Selecting the Correct Answer**: Based on the definitions, the part of the Earth that supports life is the **Biosphere**. Therefore, the correct answer is **Option D**.

5. **Conclusion**: The biosphere is crucial as it encompasses all ecosystems and is where all living organisms interact with each other and their environment.

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