Water Hyacinth is termed as 'terror of Bengal' it causes death of fish because it.

Options

A. Covers water surface and inhabits sunlight to pass through
B. Drains oxygen from water that causes oxygen deficiency
C. Absorbs nutrients from water that causes malnutrition
D. Releases `CO_(2)` in huge amount which is lethal to fish.

Answer

**Step-by-Step Solution:**

1. **Understanding Water Hyacinth**: Water hyacinth is an aquatic weed that grows rapidly in water bodies. It is known for its ability to cover the surface of water bodies, which can lead to various ecological issues.

2. **Impact on Sunlight**: One of the primary problems caused by water hyacinth is that it covers the surface of water bodies. This dense mat of vegetation inhibits sunlight from penetrating the water, which can affect the growth of aquatic plants that rely on sunlight for photosynthesis.

3. **Oxygen Depletion**: Water hyacinth absorbs dissolved oxygen from the water for its own metabolic processes. This leads to a significant reduction in the amount of dissolved oxygen available in the water.

4. **Effect on Fish**: Fish and other aquatic organisms rely on dissolved oxygen for respiration. When water hyacinth drains the oxygen from the water, it creates an oxygen-deficient environment. This deficiency can lead to the death of fish, as they cannot survive without sufficient oxygen.

5. **Ecological and Economic Consequences**: The death of fish not only disrupts the aquatic ecosystem but also has serious implications for the local economy, especially in regions like Bengal where fish is a staple food and an important source of livelihood.

6. **Conclusion**: Therefore, the correct answer to the question is that water hyacinth is termed the 'terror of Bengal' because it drains oxygen from water, causing oxygen deficiency that leads to the death of fish.

**Final Answer**: Water hyacinth is termed as 'terror of Bengal' because it drains oxygen from water, causing oxygen deficiency.

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