Nine-tenth of all photosynthesis of the world is carried out by:

Options

A. herbs
B. algae of oceans
C. trees with large canopy
D. shrubs

Explanation

### 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 and oxygen.

2. **Identifying Contributors to Photosynthesis**: While we often think of terrestrial plants (like trees and shrubs) as the primary contributors to photosynthesis, it is important to consider other organisms as well.

3. **Considering Aquatic Organisms**: A significant portion of photosynthesis occurs in aquatic environments. This includes various types of algae and phytoplankton that thrive in oceans and other water bodies.

4. **Recognizing the Dominance of Algae**: Research indicates that a large majority of photosynthesis, approximately 85-90%, is conducted by these aquatic organisms, particularly phytoplankton and algae, rather than terrestrial plants.

5. **Conclusion**: Therefore, the correct answer to the question is that nine-tenths of all photosynthesis in the world is carried out by algae in the oceans.

### Final Answer:
**Nine-tenths of all photosynthesis of the world is carried out by algae in the oceans.**

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