Tube feet are characteristic of phylum

Options

A. Arthropoda
B. Annelida
C. Echinodermata
D. Mollusca.

Answer

**Step-by-Step Solution:**

1. **Understanding Tube Feet**: Tube feet are specialized structures found in certain marine organisms. They are part of a unique system known as the water vascular system.

2. **Identifying the Water Vascular System**: The water vascular system, also referred to as the ambulacral system, is crucial for various functions such as locomotion, feeding, and respiration in certain organisms.

3. **Function of Tube Feet**: Tube feet operate by filling with water, which allows them to extend and contract. This mechanism is vital for movement (locomotion), capturing food, and facilitating gas exchange (respiration).

4. **Determining the Phylum**: The question asks which phylum is characterized by tube feet. The options provided are:
- A) Arthropoda
- B) Annelida
- C) Echinodermata
- D) Mollusca

5. **Analyzing Each Option**:
- **Arthropoda**: Characterized by jointed appendages and segmented bodies, not tube feet.
- **Annelida**: Known for metameric segmentation, which does not include tube feet.
- **Echinodermata**: This phylum includes organisms like starfish and sea urchins, which possess tube feet as part of their water vascular system.
- **Mollusca**: Generally soft-bodied organisms, often with shells, and do not have tube feet.

6. **Conclusion**: Based on the analysis, the correct answer is **C) Echinodermata**, as tube feet are a distinctive feature of this phylum.

**Final Answer**: Tube feet are characteristic of phylum **Echinodermata**.

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