Name the process by which the sun's energy is trapped as the source of energy used by virtually all living organisms :

Options

A. metabolism
B. glycolysis
C. homeostasis
D. photosynthesis

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the process by which the sun's energy is captured and used as a source of energy by living organisms.

2. **Identifying Key Terms**: The key term in the question is "sun's energy." This indicates that we are looking for a process that involves capturing solar energy.

3. **Reviewing the Options**:
- **Metabolism**: This refers to all the chemical reactions that occur within living organisms to maintain life. It does not specifically relate to capturing solar energy.
- **Glycolysis**: This is a specific metabolic pathway that breaks down glucose to produce energy. It does not involve the capture of solar energy.
- **Homeostasis**: This is the process by which organisms maintain a stable internal environment. It is unrelated to capturing energy from the sun.
- **Photosynthesis**: This is the process by which green plants and some other organisms convert light energy (from the sun) into chemical energy, specifically glucose, using carbon dioxide and water.

4. **Selecting the Correct Answer**: Given that photosynthesis is the only process that directly involves capturing solar energy and converting it into a usable form (chemical energy), the correct answer to the question is **photosynthesis**.

5. **Conclusion**: Therefore, the process by which the sun's energy is trapped as the source of energy used by virtually all living organisms is **photosynthesis**.

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