Nine-tenth of al photosynthesis of world (85-90%) is carried out by

Options

A. Large trees with millions of branches and leaves
B. algae of the ocean chlorophyll containing ferns of the forest
C. chlorophyll containing ferns of the forest
D. scientists in the laboratories

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the major contributors to photosynthesis on Earth, specifically identifying which organisms carry out 85-90% of the total photosynthesis.

2. **Identifying Key Organisms**: It is known that photosynthesis is primarily conducted by plants, algae, and phytoplankton. Among these, phytoplankton and algae in the oceans are particularly abundant.

3. **Analyzing Contribution**: Research indicates that phytoplankton, which are microscopic organisms found in oceans, contribute significantly to global photosynthesis. They are responsible for approximately 85-90% of the total photosynthesis on Earth.

4. **Considering Other Contributors**: While land plants, including trees and rainforests, do contribute to photosynthesis, their contribution is relatively smaller, estimated at around 10% of the total.

5. **Conclusion**: Based on the evidence, it can be concluded that the majority of photosynthesis (85-90%) is carried out by algae and phytoplankton in the oceans.

**Final Answer**: Approximately 85-90% of photosynthesis is carried out by algae and phytoplankton in the oceans.

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