Which of the following statements is true about water hyacinth?

Options

A. It gives useful products to be used in medicine
B. It is a marine plant
C. It takes oxygen from water which causes death of fishes
D. It is being cultivated in sea water for biogas

Answer

**Step-by-Step Solution:**

1. **Understanding Water Hyacinth**: Water hyacinth is a floating aquatic plant known for its rapid growth and ability to cover large areas of water bodies.

2. **Evaluating the Statements**:
- **Option 1**: "It gives useful products to use in medicine."
- This statement is incorrect. Water hyacinth is not known for any medicinal uses.

- **Option 2**: "It is a marine plant."
- This statement is also incorrect. Water hyacinth is not a marine plant; it thrives in freshwater environments.

- **Option 3**: "It takes oxygen from water which causes death of fishes."
- This statement is correct. Water hyacinth has a high propagation capacity, leading to dense growth that depletes oxygen in the water, which can result in the death of fish and other aquatic organisms.

- **Option 4**: "It is being cultivated in seawater for biogas."
- This statement is incorrect. Water hyacinth is not cultivated in seawater; it is typically found in freshwater.

3. **Conclusion**: After evaluating all options, the true statement about water hyacinth is option 3: "It takes oxygen from water which causes death of fishes."

**Final Answer**: Option 3 is the correct statement about water hyacinth.

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