Locomotory organs of Nereis are

Options

A. suckers
B. setae
C. parapodia
D. jointed legs

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about the locomotory organs of Nereis, which is a genus of marine polychaete worms belonging to the phylum Annelida.

2. **Understand the Characteristics of Nereis**: Nereis is an aquatic organism, and it is important to note that it has specific adaptations for locomotion in water.

3. **Evaluate the Options**: The options provided are suckers, siti, parapodia, and jointed legs. We need to analyze each option to determine which one is correct for Nereis.

4. **Analyze Each Option**:
- **Suckers**: These are typically found in some annelids but are not the primary locomotory organs for Nereis.
- **Siti (Setae)**: While setae are present in annelids, they are not the main locomotory structures for Nereis.
- **Jointed Legs**: This feature is characteristic of arthropods, not annelids, making this option incorrect for Nereis.
- **Parapodia**: These are paired, lateral extensions found on each segment of Nereis. They are crucial for locomotion, as they help the worm swim and move through its aquatic environment.

5. **Conclusion**: After evaluating all the options, the correct answer for the locomotory organs of Nereis is **parapodia**.

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