Which of the following is an echinoderm ?

Options

A. Sea lemon
B. Sea fan
C. Sea hare
D. Sea urchin

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks which of the given options is an echinoderm.

2. **Understand Echinoderms**: Echinoderms belong to the phylum Echinodermata. The term "Echinodermata" can be broken down into two parts: "Echino" meaning spiny and "Dermata" meaning skin. Therefore, echinoderms are characterized by having spiny skin.

3. **Examine the Options**: The options provided are:
- C lemon
- C fan
- C hill
- C urchin

4. **Analyze Each Option**:
- **C lemon**: This is a type of mollusk, specifically belonging to the genus Daudite.
- **C fan**: This is known as Gorgonia and belongs to the phylum Mediria (Cnidaria).
- **C hill**: This is also a mollusk, specifically a gastropod.
- **C urchin**: This is the only option that belongs to the phylum Echinodermata and has spiny skin.

5. **Conclusion**: Based on the analysis, the correct answer is **C urchin**, as it is the only option that is an echinoderm.

**Final Answer**: C urchin

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