The technique used for separation of DNA fragment is:

Options

A. autoradiography
B. gel electrophoresis
C. microinjection
D. gel-filtration chromatography

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the technique used for the separation of DNA fragments.

2. **Analyzing the Options**:
- **Option A: Autoradiography**: This is an imaging technique that uses radioactive materials to visualize samples. It does not separate DNA fragments.
- **Option B: Gel Electrophoresis**: This is a molecular technique that separates biomolecules, including DNA, based on their size. DNA fragments move through a gel in response to an electric current, with smaller fragments moving faster than larger ones.
- **Option C: Microinjection**: This technique involves injecting substances, such as DNA, into living cells using a micropipette. It does not separate DNA fragments.
- **Option D: Gel Filtration Chromatography**: Also known as size exclusion chromatography, this technique separates molecules based on size but is not specifically used for separating DNA fragments.

3. **Identifying the Correct Technique**: After analyzing all the options, it is clear that gel electrophoresis is specifically designed for the separation of DNA fragments based on their size.

4. **Conclusion**: The technique used for the separation of DNA fragments is **gel electrophoresis**.

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