Pick out the odd one on the basis of phylum:-

Options

A. Nereis
B. Pheretima
C. Hirudinaria
D. Wuchereria

Answer

To solve the question of picking out the odd one based on phylum, we need to analyze the given options and identify their respective phyla.

### Step-by-Step Solution:

1. **Identify the First Option (Nerys)**:
- Nerys is an aquatic organism that belongs to the phylum **Annelida**.
- Annelids are segmented worms.

2. **Identify the Second Option (Ferritima)**:
- Ferritima is commonly known as an earthworm, which is also a member of the phylum **Annelida**.
- Earthworms are monoecious, meaning they have both male and female reproductive organs.

3. **Identify the Third Option (Herudinaria)**:
- Herudinaria is a blood-sucking leech, which again belongs to the phylum **Annelida**.
- Leeches are also segmented worms and are classified under the same phylum as Nerys and Ferritima.

4. **Identify the Fourth Option (Butchereria)**:
- Butchereria is a filarial worm, which belongs to the phylum **Aschelminthes** (also known as Nematoda).
- Filarial worms are known to cause diseases such as Elephantiasis and are not segmented worms like the others.

5. **Conclusion**:
- The first three options (Nerys, Ferritima, and Herudinaria) all belong to the phylum **Annelida**.
- The fourth option (Butchereria) belongs to the phylum **Aschelminthes**.
- Therefore, the odd one out based on phylum is **Butchereria**.

### Final Answer:
The odd one out is **Butchereria**.

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