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

Options

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

Answer

To solve the question regarding the technique used for the extraction of DNA fragments from a gel, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the specific technique used to extract DNA fragments from a gel after they have been separated.

2. **Review the Options**: The options provided are:
- A) Centrifugation
- B) Illusion
- C) Transfection
- D) Gel electrophoresis

3. **Evaluate Each Option**:
- **Centrifugation**: This technique is used to separate particles from a solution based on density but is not specifically for extracting DNA from gels. Therefore, this option is incorrect.
- **Illusion**: This is the correct answer. Illusion refers to the technique used to extract DNA fragments from the gel after electrophoresis.
- **Transfection**: This technique involves introducing nucleic acids into eukaryotic cells and is not related to gel extraction. Thus, this option is incorrect.
- **Gel Electrophoresis**: This is the method used to separate DNA fragments based on size but does not refer to the extraction process itself. Hence, this option is also incorrect.

4. **Select the Correct Answer**: Based on the evaluation, the correct answer is **Illusion**.

### Final Answer:
The technique of extraction of DNA fragments from the gel is called **Illusion**.