Which is a ciliate protist

Options

A. Euglena
B. Vorticella
C. Pelomyxa
D. Metopus.

Answer

### Step-by-Step Solution:

1. **Understand the Question**: The question asks to identify a ciliate protist from the given options.

2. **Review the Options**: The options provided are:
- Euglena
- Vorticella
- Pelomyxa
- Metopus

3. **Define Ciliate Protists**: Ciliate protists are eukaryotic organisms that possess cilia, which are hair-like structures that aid in movement and attachment to substrates.

4. **Analyze Each Option**:
- **Euglena**: This organism does not have cilia; instead, it has flagella for movement. Thus, it is not a ciliate protist.
- **Vorticella**: This organism is a ciliated protist that belongs to the phylum Ciliophora. It has cilia for locomotion and can be found in both freshwater and saltwater environments.
- **Pelomyxa**: This organism also does not have cilia; it possesses flagella, making it an incorrect option.
- **Metopus**: This is not classified as a protist, so it is also not a ciliate.

5. **Conclusion**: The only organism from the options that qualifies as a ciliate protist is **Vorticella**.

### Final Answer:
The ciliate protist is **Vorticella**.

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