Maximum contribution of oxgyen is got from

Options

A. grasslands
B. phytoplankton
C. dense forests
D. herbs and shrubs

Answer

To solve the question regarding the maximum contribution of oxygen, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks which source contributes the most oxygen among the given options: grassland, phytoplankton, dense forests, or herbs and shrubs.

2. **Review Photosynthesis**: Recall that photosynthesis is the process by which plants convert carbon dioxide and water into glucose and oxygen, using sunlight and chlorophyll. The general equation for photosynthesis is:
\[ 6CO_2 + 6H_2O \xrightarrow{light} C_6H_{12}O_6 + 6O_2 \]
This indicates that oxygen (O₂) is a byproduct of this process.

3. **Evaluate the Options**:
- **Grasslands**: While they do contribute to oxygen production, they are not as significant as other sources.
- **Phytoplankton**: These are microscopic organisms in aquatic environments that perform photosynthesis. They are known to produce a substantial amount of oxygen.
- **Dense Forests**: They are significant contributors to oxygen production on land but not as much as phytoplankton in total.
- **Herbs and Shrubs**: Similar to grasslands, they contribute but are less significant than forests and phytoplankton.

4. **Identify the Major Contributor**: Research and scientific consensus indicate that phytoplankton in the oceans are responsible for producing approximately 50-80% of the Earth's oxygen. This is due to their vast numbers and the extensive surface area of the oceans.

5. **Conclusion**: Based on the understanding of photosynthesis and the evaluation of the options, the maximum contribution of oxygen is from **phytoplankton**.

### Final Answer:
The maximum contribution of oxygen is obtained from **phytoplankton**.

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