Which of the following weed has become a major cause of pollen allergy in india ?

Options

A. pistia
B. myosotis
C. parthenium
D. mirabills

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which weed has become a major cause of pollen allergy in India. We need to analyze the given options to identify the correct weed.

2. **Analyzing Option 1 - Pistia**:
- Common Name: Water Lettuce
- Description: An aquatic plant that is invasive in nature.
- Conclusion: While it is harmful to aquatic ecosystems, it is not known to cause pollen allergies. Therefore, this option is not the answer.

3. **Analyzing Option 2 - Myosotis**:
- Common Name: Forget-me-not
- Description: This plant is primarily known for causing fungal infections.
- Conclusion: It does not have a significant association with pollen allergies. Thus, this option is also not the answer.

4. **Analyzing Option 3 - Parthenium**:
- Common Name: Congress Grass
- Description: This weed is known for being highly toxic and has multiple harmful effects, including causing pollen allergies.
- Conclusion: Given its significant impact on health, especially in terms of allergies, this is a strong candidate for the answer.

5. **Analyzing Option 4 - Mirabilis**:
- Common Name: Four O'Clock Plant
- Description: This plant is harmful to the gut and skin of humans.
- Conclusion: It does not cause pollen allergies, making this option incorrect as well.

6. **Final Conclusion**: After analyzing all options, the weed that has become a major cause of pollen allergy in India is **Parthenium (Congress Grass)**.

**Final Answer**: Parthenium (Congress Grass)

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