Viruses that affect bacteria are ________.

Options

A. protozoan
B. parasites
C. bacteriophage
D. plasmodium

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks about viruses that specifically affect bacteria.

2. **Identify the Options**: The options given are:
- Option 1: Protozoan
- Option 2: Parasite
- Option 3: Bacteriophage
- Option 4: Plasmodium

3. **Analyze Each Option**:
- **Protozoan**: These are unicellular organisms and are living entities. They do not affect bacteria.
- **Parasite**: Parasites are organisms that live on or in a host organism. They typically affect living organisms and do not specifically target bacteria.
- **Bacteriophage**: This term refers to viruses that specifically infect and kill bacteria. The name itself indicates that it is a virus that targets bacteria.
- **Plasmodium**: This is a genus of protozoan parasites that cause malaria in humans. It does not affect bacteria.

4. **Conclusion**: Based on the analysis, the only option that correctly identifies a virus that affects bacteria is **Bacteriophage**.

5. **Final Answer**: Viruses that affect bacteria are **Bacteriophage**.

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