the percularity of sponges is

Options

A. Canal system
B. Water vascular system
C. Central gastro vascular cavity
D. Bioluminescence

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the peculiarities of sponges. We need to identify a unique feature that distinguishes sponges from other animals.

2. **Identifying the Characteristics of Sponges**: Sponges are simple, multicellular organisms that belong to the phylum Porifera. Some of their notable characteristics include:
- They are non-motile, meaning they do not move and are attached to a solid substrate.
- They possess numerous pores (ostia) on their body surface.

3. **Recognizing the Canal System**: One of the most significant features of sponges is their canal system. This system is composed of a network of canals and chambers that facilitate the flow of water through the sponge. The water enters through the pores, circulates through the canals, and exits through a larger opening called the osculum.

4. **Evaluating the Options**: The question provides four options:
- Canal system
- Water vascular system
- Central gastrovascular cavity
- Bioluminescence

Among these options, we need to determine which one is a unique feature of sponges.

5. **Analyzing Each Option**:
- **Canal system**: This is indeed a characteristic feature of sponges, as it helps in the circulation of water and nutrients.
- **Water vascular system**: This feature is found in echinoderms (like starfish), not in sponges.
- **Central gastrovascular cavity**: This is a feature of cnidarians (like jellyfish), not sponges.
- **Bioluminescence**: While some organisms can exhibit bioluminescence, it is not a defining characteristic of sponges.

6. **Conclusion**: Based on the analysis, the correct answer is the canal system, as it is the peculiar feature that distinguishes sponges from other animal groups.

**Final Answer**: The peculiarity of sponges is their canal system.

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