The organisms that can be stored as crystals are:

Options

A. virus
B. bacteria
C. algae
D. fungi

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about organisms that can be stored in the form of crystals. This implies we are looking for a specific type of organism that can exist in a crystalline state.

2. **Identifying Types of Microorganisms**: The main types of microorganisms include bacteria, algae, fungi, and viruses. We need to analyze which of these can be stored as crystals.

3. **Analyzing Bacteria, Algae, and Fungi**:
- Bacteria: These are living organisms that cannot be stored as crystals. They require a living environment to survive.
- Algae: Similar to bacteria, algae are also living organisms and cannot be stored in a crystalline form.
- Fungi: Like bacteria and algae, fungi are living organisms that do not exist in a crystalline state.

4. **Understanding Viruses**: Viruses are unique because they can exist in two states:
- Living: When inside a host organism, they utilize the host's cellular machinery to replicate and carry out their life processes.
- Non-living: Outside a host, viruses become inactive and can form crystalline structures.

5. **Conclusion**: Based on the analysis, the only type of microorganism that can be stored as crystals is viruses. Therefore, the answer to the question is **viruses**.

### Final Answer:
The organisms that can be stored as crystals are **viruses**.

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