Hay fever is caused by

Options

A. Heptitis
B. Dangue
C. Allergy
D. Helper T-cells

Answer

**Step-by-Step Solution:**

1. **Understanding Hay Fever**: Hay fever, also known as allergic rhinitis, is an allergic reaction that occurs when the immune system overreacts to allergens in the air.

2. **Identifying the Cause**: The primary cause of hay fever is exposure to pollen from plants. This includes pollen from grasses, trees, and weeds.

3. **Recognizing Symptoms**: Common symptoms of hay fever include sneezing, runny nose, itchy eyes, and throat irritation. These symptoms occur due to the body's immune response to the allergens.

4. **Considering the Options**: The question provides four options:
- Hepatitis
- Dengue
- Allergy
- Alpha T cells

5. **Analyzing Each Option**:
- **Hepatitis**: A viral infection affecting the liver, not related to hay fever.
- **Dengue**: A viral disease transmitted by mosquitoes, unrelated to hay fever.
- **Allergy**: This is the correct answer as hay fever is a type of allergic reaction.
- **Alpha T cells**: These are immune cells that help in the immune response but are not the cause of hay fever.

6. **Conclusion**: Based on the information analyzed, hay fever is caused by an allergy, specifically to pollen from various plants.

**Final Answer**: Hay fever is caused by **allergy**.

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