A characteristic feature of ctenophores is

Options

A. fresh water habitat
B. asexual reproduction
C. locomotion by ciliated comb plates
D. absence of larval form

Answer

### Step-by-Step Solution:

1. **Identify the Organism**: The question asks about a characteristic feature of ctenophores. Ctenophores, also known as comb jellies, are marine animals.

2. **Understand the Structure**: Ctenophores are known for their unique structure. They possess a comb-like ciliary plate, which is a distinctive feature of these organisms.

3. **Function of the Structure**: The ciliary plates are used for locomotion. The cilia beat in a coordinated manner, allowing ctenophores to swim through the water.

4. **Reproduction Method**: Ctenophores reproduce sexually, with the fusion of gametes occurring externally in the water. This is an important characteristic that differentiates them from organisms that reproduce asexually.

5. **Larval Form**: Ctenophores do not have a larval form, which is another characteristic feature. However, this option is not the main characteristic that defines them.

6. **Conclusion**: The primary characteristic feature of ctenophores is their locomotion by ciliated comb plates.

### Final Answer:
A characteristic feature of ctenophores is locomotion by ciliated comb plates.

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