The eutrophication of water body results in :

Options

A. loss of Biodiversity
B. breakdown of organic matter
C. increase in biodiversity
D. decrease in BOD .

Explanation

**Step-by-Step Solution:**

1. **Understanding Eutrophication**: Eutrophication is a process that occurs in water bodies when they receive excess nutrients, particularly nitrogen and phosphorus. These nutrients often come from agricultural runoff, sewage discharge, and other sources.

2. **Nutrient Enrichment**: The increase in nutrients leads to a rapid growth of algae and aquatic plants, known as algal blooms. These blooms can cover the surface of the water, blocking sunlight from reaching other aquatic plants.

3. **Depletion of Oxygen**: As the algae die and decompose, the decomposition process consumes a significant amount of dissolved oxygen in the water. This depletion of oxygen creates hypoxic (low oxygen) conditions.

4. **Impact on Aquatic Life**: The lack of oxygen in the water leads to the death of fish and other aquatic organisms that rely on oxygen for survival. This results in a decline in biodiversity within the aquatic ecosystem.

5. **Conclusion**: Therefore, the eutrophication of a water body primarily results in the loss of biodiversity due to the death of aquatic life caused by oxygen depletion.

**Final Answer**: The eutrophication of a water body results in the loss of biodiversity.

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