The technique of extraction of DNA fragments from the gel is called:

Options

A. Centrifugation
B. Elution
C. Transfection
D. Gel electrophoresis

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks for the technique used to extract DNA fragments from a gel.

2. **Analyze the Options**:
- **Option 1: Centrifugation**: This technique is used to separate particles from a solution based on their size and density. It is not specifically used for extracting DNA fragments from a gel. Therefore, this option is incorrect.

- **Option 2: Elution**: This is the process of extracting one material from another by washing with a solvent. In the context of DNA extraction from a gel, elution refers to the process of recovering DNA fragments from the gel matrix after electrophoresis. This option is correct.

- **Option 3: Transfection**: This process involves introducing nucleic acids into eukaryotic cells, typically for research or therapeutic purposes. It does not relate to the extraction of DNA from a gel, making this option incorrect.

- **Option 4: Gel Electrophoresis**: This is a method used to separate macromolecules, such as DNA, based on their size. It is not the technique used to extract DNA from the gel, hence this option is also incorrect.

3. **Conclusion**: Based on the analysis of the options, the correct answer is **Option 2: Elution**. This is the technique used to extract DNA fragments from the gel.

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