American water plant that has become a troublesome water weed in India is

Options

A. Cyperus rotundus
B. Eichhornia crassipes
C. Trapa latifolia
D. Trapa bispinosa

Explanation

**Step-by-Step Solution:**

1. **Identify the Question:** The question asks for the name of an American water plant that has become a troublesome water weed in India.

2. **Understand the Context:** The question refers to an aquatic plant that was introduced to India and has since become problematic.

3. **Recognize the Plant:** The American water plant in question is commonly known as water hyacinth.

4. **Scientific Name:** The scientific name of water hyacinth is *Eichhornia crassipes*.

5. **Impact of the Plant:** Water hyacinth is known for forming dense mats in water bodies, which reduces oxygen levels for other aquatic organisms, causing harm to the ecosystem.

6. **Conclusion:** Based on the information, the correct answer to the question is *Eichhornia crassipes*.

**Final Answer:** The American water plant that has become a troublesome water weed in India is *Eichhornia crassipes*.

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