An echinoderms is

Options

A. Torpedo Fish
B. Star Fish
C. Electric Ray
D. Shark.

Answer

**Step-by-Step Solution:**

1. **Understanding Echinoderms**: Echinoderms are a group of marine animals characterized by their radial symmetry, a water vascular system, and a calcareous endoskeleton. They belong to the phylum Echinodermata.

2. **Identifying the Options**: The options given are:
- Torpedo fish
- Starfish
- Electric ray
- Shark

3. **Classifying the Options**:
- **Torpedo Fish**: This fish belongs to the phylum Chordata, which includes all vertebrates.
- **Electric Ray**: This is another name for the torpedo fish and also belongs to the phylum Chordata.
- **Shark**: Sharks are also vertebrates and belong to the phylum Chordata.

4. **Identifying the Correct Answer**: The only option that belongs to the phylum Echinodermata is the starfish. Starfish, also known as sea stars, belong to the class Asteroidea within the phylum Echinodermata.

5. **Conclusion**: Therefore, the correct answer to the question "An echinoderm is" is **starfish**.

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