Kala-azar disease is caused by

Options

A. Trypanosoma gambiense
B. Wuchereria bancrofti
C. Leishmania donovani
D. Taenia sloium

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the causative agent of the disease Kala-azar.

2. **List the Options**: The options provided are:
- a) Trypanosoma gambiense
- b) Wuchereria bancrofti
- c) Leishmania donovani
- d) Taenia solium

3. **Analyze Each Option**:
- **Option a: Trypanosoma gambiense**: This organism is known to cause African sleeping sickness, not Kala-azar.
- **Option b: Wuchereria bancrofti**: This is a roundworm that causes elephantiasis (filariasis), not Kala-azar.
- **Option c: Leishmania donovani**: This protozoan is known to cause Leishmaniasis, which is synonymous with Kala-azar.
- **Option d: Taenia solium**: This is a tapeworm that causes taeniasis, not Kala-azar.

4. **Conclusion**: After analyzing the options, it is clear that the correct answer is **Leishmania donovani**, as it is the organism responsible for causing Kala-azar.

5. **Final Answer**: Kala-azar disease is caused by **Leishmania donovani**.

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