The causal organism of filariasis/elephantiasis is:

Options

A. Wuchereria bancrofti
B. Trichophyton
C. Entamoeba histolytica
D. Ascaris lumbricoides

Answer

To determine the causal organism of filariasis (also known as elephantiasis), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Disease**: Understand that filariasis is a disease characterized by the swelling of body parts, often the limbs, due to the obstruction of lymphatic vessels.

2. **Understand the Causal Organism**: Recognize that filariasis is caused by a type of parasitic worm known as a filarial worm.

3. **List the Options**: The options provided are:
- Victoriae Bancroftii
- Trichophyton
- Antamoebae Histolytica
- Ascaris Lumbricoides

4. **Analyze Each Option**:
- **Victoriae Bancroftii**: This is a filarial worm and is known to cause filariasis.
- **Trichophyton**: This is a fungus responsible for ringworm disease, not filariasis.
- **Antamoebae Histolytica**: This is a protozoan responsible for amoebiasis, not filariasis.
- **Ascaris Lumbricoides**: This is a roundworm responsible for ascariasis, not filariasis.

5. **Determine the Correct Answer**: Based on the analysis, the correct causal organism for filariasis/elephantiasis is **Victoriae Bancroftii**.

### Final Answer:
The causal organism of filariasis/elephantiasis is **Victoriae Bancroftii**.

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