Water vascular system and tube feet is the characteristic of -

Options

A. Arthropoda
B. Echinodermata
C. Molluscs
D. Bony fishes

Answer

**Step-by-Step Solution:**

1. **Identify the Key Terms**: The question mentions "water vascular system" and "tube feet." These are specific biological structures and systems.

2. **Understand the Function**: The water vascular system is a unique feature that aids in locomotion and respiration in certain organisms. It operates through hydraulic pressure.

3. **Recall the Relevant Phylum**: The water vascular system is characteristic of Echinoderms, which belong to the phylum Echinodermata. This phylum includes organisms such as starfish, sea urchins, and sea cucumbers.

4. **Eliminate Incorrect Options**:
- Arthropoda: This phylum includes insects, arachnids, and crustaceans, which do not have a water vascular system.
- Mollusk: This phylum includes snails, clams, and octopuses, which also lack a water vascular system.
- Bonifish (likely a typo for "bony fish"): This group of fish does not possess a water vascular system.

5. **Conclude the Answer**: Since the water vascular system and tube feet are unique to Echinoderms, the correct answer is **Echinodermata**.

**Final Answer**: The water vascular system and tube feet are characteristics of **Echinodermata**.

---