The one which does not lose its identity even after crystallisation is

Options

A. Virus
B. Bacterium
C. Microbe
D. Protistan

Answer

To solve the question "The one which does not lose its identity even after crystallisation is," we can follow these steps:

### Step 1: Understand the Question
The question is asking which entity retains its identity after undergoing the process of crystallization.

### Step 2: Define Crystallization
Crystallization is a process where a substance is transformed into a solid crystal form. In the context of biological entities, it often refers to the ability to organize and study the molecular structure of these entities.

### Step 3: Analyze the Options
The options provided are:
1. Virus
2. Bacterium
3. Microbe
4. Protistin

### Step 4: Evaluate Each Option
- **Virus**: Viruses can be crystallized, and their molecular structure can be studied without losing their identity. This is a key characteristic of viruses.
- **Bacterium**: Bacteria typically do not retain their identity after crystallization; they can lose their structural integrity.
- **Microbe**: This is a broad term that includes bacteria, viruses, fungi, etc. Most microbes do not retain their identity after crystallization.
- **Protistin**: Protists, like bacteria, generally lose their identity when crystallized.

### Step 5: Conclusion
Based on the analysis, the only entity that retains its identity even after crystallization is the **virus**.

### Final Answer
The correct answer is **virus**.

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