Which of the following weed should be eradicated quickly ?

Options

A. Opuntia
B. Eichhornia
C. Parthenium
D. Vallisneria

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks which weed should be eradicated quickly among the given options.

2. **Defining Weeds:**
Weeds are unwanted plants that grow in agricultural fields and compete with crops for resources such as nutrients, water, and light. Some weeds can also spread diseases.

3. **Analyzing the Options:**
- **Option 1: Opuntia (Prickly Pear Cactus)**
- Opuntia is a cactus that is often grown for ornamental purposes. It is not considered a weed because it is cultivated intentionally.
- **Conclusion:** This option is incorrect.

- **Option 2: Acornia (Water Hyacinth)**
- Acornia, commonly known as water hyacinth, is an aquatic plant that can be harmful to aquatic ecosystems. However, it does not compete with terrestrial crops.
- **Conclusion:** This option is also incorrect as it does not fit the typical definition of a weed that competes with crops.

- **Option 3: Parthenium**
- Parthenium is a well-known weed that is harmful to crops. It reduces the growth of several crop plants and its pollen can cause pulmonary infections in humans.
- **Conclusion:** This is a dangerous weed that should be eradicated quickly. This option is correct.

- **Option 4: Wallisneria**
- Wallisneria is another aquatic plant that is not considered dangerous. It does not pose significant threats to crops or ecosystems.
- **Conclusion:** This option is incorrect as it does not need to be eradicated quickly.

4. **Final Answer:**
Based on the analysis, the weed that should be eradicated quickly is **Option 3: Parthenium**.

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