Eosinophilia is caused by `:-`

Options

A. Teniasis
B. Ascariaris
C. Hay fever
D. All of above

Answer

### Step-by-Step Solution:

1. **Understanding Eosinophilia**:
- Eosinophilia is a condition characterized by an increased number of eosinophils, a type of white blood cell, in the bloodstream.

2. **Causes of Eosinophilia**:
- Eosinophilia can be caused by various factors, including infections, allergies, and certain diseases.
- In this context, the question lists several potential causes: teniasis, ascariasis, and hay fever.

3. **Explaining Each Cause**:
- **Teniasis**: This is an infection caused by tapeworms, which can lead to an increase in eosinophils as the body reacts to the foreign organism.
- **Ascariasis**: This is caused by the roundworm Ascaris lumbricoides. Similar to teniasis, the body’s immune response to the parasite can result in eosinophilia.
- **Hay Fever**: Also known as allergic rhinitis, this is an allergic reaction to pollen or other allergens, which can also trigger an increase in eosinophils.

4. **Conclusion**:
- Since all three conditions (teniasis, ascariasis, and hay fever) can lead to eosinophilia, the correct answer to the question is "all of the above".

### Final Answer:
Eosinophilia is caused by teniasis, ascariasis, hay fever, or all of the above. The correct answer is **all of the above**.

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