Sycon belongs to a group of animals which are best described as

Options

A. multicellular with a gastrovascular system
B. multicellular having tissue organisation, but no body cavity
C. unicellular or acellular
D. multicellular without any tissue organisation

Explanation

To answer the question regarding the classification of Sycon, we need to analyze the characteristics of this organism and the options provided.

### Step-by-Step Solution:

1. **Identify the Classification of Sycon**:
Sycon is a type of sponge, which belongs to the phylum Porifera.

2. **Understand the Characteristics of Porifera**:
- Sponges are known as the most primitive multicellular organisms.
- They have a simple body structure characterized by numerous pores (hence the name "pore-bearers").
- They exhibit a cellular level of organization but do not have true tissues.

3. **Evaluate the Options Given**:
- **Option 1**: Multicellular with gastrovascular systems - This is incorrect as sponges do not have a gastrovascular cavity.
- **Option 2**: Multicellular having tissue organization, but no body cavity - This is incorrect because sponges do not have true tissue organization.
- **Option 3**: Unicellular or acellular - This is incorrect as Sycon is multicellular.
- **Option 4**: Multicellular and without any tissue organization - This is correct as sponges are multicellular but lack true tissue organization.

4. **Conclusion**:
Based on the characteristics of Sycon and the analysis of the options, the correct answer is that Sycon belongs to a group of animals which are best described as multicellular and without any tissue organization.

### Final Answer:
Sycon belongs to a group of animals which are best described as multicellular and without any tissue organization.

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