_________ are non-living organisms.

Options

A. Bacteria
B. Virus
C. Protozoa
D. Algae

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks for an example of non-living organisms. We need to identify which of the given options is considered non-living.

2. **Identifying the Options:** The options provided are:
- A) Bacteria
- B) Virus
- C) Protozoa
- D) Algae

3. **Defining Microorganisms:** Microorganisms are tiny organisms that can only be seen under a microscope. They can be beneficial or harmful to humans and the environment.

4. **Analyzing Each Option:**
- **Bacteria:** These are living organisms that can reproduce and carry out metabolic processes.
- **Protozoa:** These are single-celled organisms that are also considered living.
- **Algae:** These are photosynthetic organisms that are classified as living.
- **Virus:** Viruses are unique because they cannot carry out life processes on their own. They require a host cell to replicate and do not exhibit characteristics of living organisms when outside a host.

5. **Conclusion:** Based on the analysis, the only option that fits the description of a non-living organism is the virus.

6. **Final Answer:** Therefore, the correct answer is **B) Virus**.

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