Filariasis is caused by

Options

A. Wuchereria bancofti
B. Glossina palpalis
C. Phlebotomus argentipes
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Filariasis**: Filariasis is a disease caused by parasitic worms. It is important to identify the specific organism responsible for this disease.

2. **Analyzing the Options**:
- **Option 1: Wuchereria bancrofti**: This organism is a type of roundworm that belongs to the class Ascaromycetes. It is known to cause filariasis, specifically elephantiasis.
- **Option 2: Glossina palpalis**: This is a type of tsetse fly that is known to transmit the Trypanosoma parasite, which causes Gambian sleeping sickness. It does not cause filariasis.
- **Option 3: Phlebotomus argentipes**: This organism is a sandfly that transmits the Leishmania parasite, causing leishmaniasis. It is not associated with filariasis.
- **Option 4: All of the above**: This option suggests that all the listed organisms cause filariasis, which is incorrect based on the analysis of the previous options.

3. **Conclusion**: Based on the analysis, only Wuchereria bancrofti is responsible for causing filariasis. Therefore, the correct answer to the question is **Wuchereria bancrofti**.

**Final Answer**: Filariasis is caused by **Wuchereria bancrofti**.

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