Pollen grain of which plants causes allergy :-

Options

A. Myosotis
B. Typha
C. Capparis
D. Parthenium

Answer

To determine which plant's pollen grain causes allergies, we will analyze the options provided and identify the one known for its allergenic properties.

### Step-by-Step Solution:

1. **Understanding Pollen Grains**: Pollen grains are microscopic structures produced by plants during reproduction. They can trigger allergic reactions in some individuals when inhaled.

2. **Identifying the Options**: The options given are:
- Myosotis
- Typha
- Caparis
- Parthenium

3. **Researching Each Plant**:
- **Myosotis**: Commonly known as forget-me-nots, these are not widely recognized for causing allergies.
- **Typha**: Also known as cattails, while they produce pollen, they are not the most common allergenic pollen.
- **Caparis**: This refers to the caper plant, which is not known for causing significant allergic reactions.
- **Parthenium**: This is commonly known as Congress grass and is notorious for causing allergic rhinitis and other allergic reactions.

4. **Conclusion**: Based on the information gathered, Parthenium is the pollen grain that is well-documented to cause allergies, particularly allergic rhinitis.

### Final Answer:
The pollen grain of **Parthenium** causes allergies.

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