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

Options

A. Unicellular with tissue level of organisation
B. Multicellular with radially symmetrical body
C. Multicellular with organ level of organisation
D. Unicellular wth bilaterally symmetrical bodies

Explanation

### Step-by-Step Solution:

1. **Identify the Organism**: The question asks about "Ctenoplana," which is commonly known as the sea walnut. It belongs to the phylum Ctenophora.

2. **Understand the Characteristics of Ctenophora**: The phylum Ctenophora is characterized by the presence of comb plates, which are rows of cilia that help in locomotion. This is a distinctive feature of comb jellies.

3. **Examine the Level of Organization**: Ctenoplana, like other members of the phylum Ctenophora, exhibits a level of organization that includes tissues and organs, which is more complex than just a cellular level.

4. **Determine the Symmetry**: Ctenophora exhibits radial symmetry, meaning that the body can be divided into multiple similar halves around a central axis. This is an important characteristic that distinguishes it from organisms with bilateral symmetry.

5. **Conclude the Best Description**: Based on the characteristics of Ctenoplana (sea walnut), it can be best described as a multicellular organism with radial symmetry and a level of organization that includes tissues and organs.

### Final Answer:
Ctenoplana belongs to a group of animals which are best described as multicellular organisms with radial symmetry.

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