Paramecium is a

Options

A. Virus
B. Bacterium
C. Annelid
D. Protozoan.

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about Paramecium, which is a well-known organism in biological studies.

2. **Consider the Options**: The options provided are virus, bacterium, analate, and protozoan. We need to determine which category Paramecium falls into.

3. **Understand Paramecium's Classification**: Paramecium is classified as a genus of unicellular organisms. It is specifically known for being ciliated, which means it has hair-like structures (cilia) that help it move.

4. **Determine the Correct Classification**:
- **Virus**: Viruses are acellular and cannot be classified as living organisms.
- **Bacterium**: Bacteria are prokaryotic and not unicellular eukaryotes like Paramecium.
- **Analate**: This term is not commonly used in biological classification.
- **Protozoan**: Protozoans are unicellular eukaryotes, and Paramecium fits this description perfectly.

5. **Conclusion**: Based on the characteristics and classification, Paramecium is best categorized as a protozoan.

**Final Answer**: Paramecium is a protozoan.

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