Which of the following belongs to phylum annelida ?

Options

A. Nereis
B. Octupus
C. Crab
D. Ant

Answer

To determine which of the given options belongs to the phylum Annelida, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Phylum Annelida**:
- Annelida is a phylum characterized by segmented bodies. The name "Annelida" comes from the Latin word "annulus," meaning little ring, which refers to the ring-like segments of their bodies.

2. **Identify the Options**:
- The options provided are:
A. Nereus
B. Octopus
C. Crab
D. Ant

3. **Analyze Each Option**:
- **A. Nereus**: This is a genus of marine polychaete worms, which belong to the phylum Annelida. They have segmented bodies and are known for their lateral appendages called parapodia.
- **B. Octopus**: Octopuses belong to the phylum Mollusca, not Annelida. They are cephalopods and do not have segmented bodies.
- **C. Crab**: Crabs are crustaceans and belong to the phylum Arthropoda. They also do not have segmented bodies in the same way that annelids do.
- **D. Ant**: Ants are insects and also belong to the phylum Arthropoda. They are not part of the Annelida phylum.

4. **Conclusion**:
- Based on the analysis, the only organism that belongs to the phylum Annelida is **A. Nereus**.

### Final Answer:
The correct answer is **A. Nereus**, which belongs to the phylum Annelida.

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