The term 'terror of Bengal' is used for

Options

A. algal bloom
B. Eichhornia crassipes
C. increased biochemical oxygen demand
D. eutrophication.

Answer

**Step-by-Step Solution:**

1. **Understanding the Term**: The term 'Terror of Bengal' refers to a specific aquatic plant that has significant negative impacts on water bodies.

2. **Identifying the Options**: The options provided are:
- Algal bloom
- Acanthophora spicifera (likely a typographical error for 'Acanthophora' or 'Eichhornia crassipes')
- Increased biological biochemical oxygen demand
- Eutrophication

3. **Recognizing the Correct Answer**: The correct answer is 'Acanthophora spicifera', which is commonly known as water hyacinth (Eichhornia crassipes). This plant is notorious for its rapid growth and negative ecological effects.

4. **Explaining the Impact**: Water hyacinth grows at an uncontrollable rate, covering water surfaces and blocking sunlight from penetrating deeper waters. This leads to:
- Reduced oxygen levels in the water, causing mass mortality of aquatic life, particularly fish.
- Disruption of the aquatic ecosystem balance.
- Acceleration of the eutrophication process, which can further degrade water quality.

5. **Conclusion**: Therefore, the term 'Terror of Bengal' is specifically used for the water hyacinth (Eichhornia crassipes) due to its detrimental effects on aquatic environments in Bengal.

**Final Answer**: The term 'Terror of Bengal' is used for **Eichhornia crassipes (water hyacinth)**.

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