Parapodia are present in

Options

A. Leech
B. Earthworm
C. Nereis
D. Housefly

Answer

**Step-by-Step Solution:**

1. **Understanding Parapodia**: Parapodia are paired, lateral outgrowths found in certain annelids. They serve primarily as locomotory organs, aiding in movement through water or substrate.

2. **Identifying the Organisms**: We need to analyze the options provided:
- A. Leech
- B. Earthworm
- C. Nereus
- D. Housefly

3. **Analyzing Each Option**:
- **Leech**: Leeches belong to the class Hirudinea within the phylum Annelida. They do not possess parapodia; instead, they move using muscular contractions.
- **Earthworm**: Earthworms are also part of the phylum Annelida but they primarily use setae (bristle-like structures) for locomotion rather than parapodia.
- **Nereus**: Nereus (often referred to as Nereis) is a marine annelid that belongs to the class Polychaeta. Polychaetes are characterized by the presence of parapodia, which they use for swimming and crawling.
- **Housefly**: Houseflies belong to the phylum Arthropoda and do not have parapodia; they have wings and legs for locomotion.

4. **Conclusion**: Based on the analysis, the organism that possesses parapodia is **C. Nereus**.

**Final Answer**: Parapodia are present in **C. Nereus**.

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