Fluid filled alveoli are formed of.

Options

A. amoebiasis
B. pneumonia
C. ascariasis
D. typhoid

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the formation of fluid-filled alveoli and which infection causes this condition.

2. **Identifying the Options**: The options provided include various infections: amoebiasis, pneumonia, ascariasis, and typhoid.

3. **Analyzing Each Option**:
- **Amoebiasis**: Caused by the protozoan *Entamoeba histolytica*, primarily affects the intestines, leading to symptoms like diarrhea with blood and mucus. It does not affect the lungs or cause fluid-filled alveoli.
- **Pneumonia**: This is a lung infection that can be caused by various organisms, including *Haemophilus influenzae* and *Streptococcus pneumoniae*. Pneumonia leads to inflammation and fluid accumulation in the alveoli, resulting in difficulty breathing and other respiratory symptoms.
- **Ascariasis**: Caused by roundworms, this infection primarily affects the intestines and is not associated with the lungs or fluid-filled alveoli.
- **Typhoid**: Caused by *Salmonella typhi*, this infection also affects the intestines and is transmitted through contaminated food and water. It does not cause fluid accumulation in the alveoli.

4. **Conclusion**: Based on the analysis, pneumonia is the only infection that leads to the formation of fluid-filled alveoli. Therefore, the correct answer is pneumonia.

### Final Answer:
Fluid-filled alveoli are formed in pneumonia.

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