Gambia fever or sleeping sickness is caused by

Options

A. Plasmodium
B. Entamoeba
C. Giardia
D. Trypanosoma.

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about Gambia fever, also known as sleeping sickness, and what causes it.

2. **Identifying the Options**: The options provided include:
- Plasmodium
- Entamoeba
- Giardia
- Trypanosoma

3. **Evaluating Each Option**:
- **Plasmodium**: This organism is known to cause malaria, not sleeping sickness. It is transmitted by the female Anopheles mosquito. Therefore, this option is incorrect.
- **Entamoeba**: This organism causes amoebiasis, which affects the large intestine. It is not related to sleeping sickness. Hence, this option is also incorrect.
- **Giardia**: This organism causes giardiasis (often referred to as Beaver fever), which is a gastrointestinal illness. This does not cause sleeping sickness, making this option incorrect as well.
- **Trypanosoma**: This is the correct organism as it causes sleeping sickness (trypanosomiasis). It affects the central nervous system and can disrupt sleep patterns, leading to the name "sleeping sickness." It is also known as Gambia fever because it was first identified in Gambia, Africa.

4. **Conclusion**: The correct answer to the question is **Trypanosoma**, as it is the causative agent of Gambia fever or sleeping sickness.

### Final Answer:
Gambia fever or sleeping sickness is caused by **Trypanosoma**.

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