In ecosystem the source of energy is

Options

A. Sun
B. Green Plants
C. Sugar produced in Photosynthesis
D. ATP

Explanation

**Step-by-Step Solution:**

1. **Understanding the Ecosystem**: An ecosystem is a geographical area that includes living organisms (plants, animals, and other organisms) and their physical environment. It consists of both biotic (living) and abiotic (non-living) components.

2. **Identifying Energy Sources**: In any ecosystem, energy is essential for the survival and functioning of organisms. The primary source of energy in most ecosystems is the sun.

3. **Role of Green Plants**: Green plants, also known as producers, utilize sunlight to perform photosynthesis. During this process, they convert solar energy into chemical energy in the form of glucose (sugar).

4. **Photosynthesis and Energy Conversion**: The sugar produced during photosynthesis serves as food for the plants. This sugar can be further converted into ATP (adenosine triphosphate), which is the energy currency of cells used by all living organisms for various biological processes.

5. **Conclusion**: Therefore, the primary source of energy in an ecosystem is the sun, as it initiates the energy flow through the process of photosynthesis in green plants.

**Final Answer**: The source of energy in the ecosystem is the sun.

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