Photosynthesis is essential for survival of

Options

A. Animals
B. Plants
C. Most of the organism
D. All the above.

Answer

### Step-by-Step Solution:

1. **Understanding Photosynthesis**:
- Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy, using carbon dioxide and water to produce glucose (sugar) and oxygen.

2. **Role of Plants**:
- Plants are the primary producers in ecosystems. They take in carbon dioxide from the atmosphere and water from the soil, and in the presence of sunlight, they produce glucose and release oxygen as a byproduct.

3. **Importance of Oxygen**:
- The oxygen produced during photosynthesis is crucial for the survival of most living organisms. Animals, including humans, rely on oxygen for respiration, which is essential for energy production in cells.

4. **Food Chain Dynamics**:
- Plants serve as the base of the food chain. Herbivores (plant-eating animals) consume plants, and carnivores (meat-eating animals) consume herbivores. This interdependence highlights the importance of plants in sustaining life.

5. **Carbon Dioxide Cycle**:
- Animals exhale carbon dioxide, which is then utilized by plants during photosynthesis. This creates a cycle where plants and animals depend on each other for survival.

6. **Conclusion**:
- Given that photosynthesis is vital for oxygen production and serves as the foundation of the food chain, it is essential for the survival of all living organisms.

7. **Final Answer**:
- Therefore, the correct answer is **D. All of the above**.