The mobile genetic element is

Options

A. Transposon
B. Mutation
C. Endonuclease
D. Variation

Answer

**Step-by-Step Solution:**

1. **Understanding Mobile Genetic Elements**: Mobile genetic elements are segments of DNA that can move around within the genome of a single cell. They can replicate and insert themselves into new locations within the DNA.

2. **Identifying the Options**: The options provided are:
- Option 1: Transposons
- Option 2: Mutation
- Option 3: Endonuclease
- Option 4: Variations

3. **Analyzing Each Option**:
- **Transposons**: These are indeed mobile genetic elements, often referred to as "jumping genes" because they can move from one location to another within the genome. They replicate via an RNA intermediate and play a role in genetic diversity and evolution.
- **Mutation**: This refers to changes in the DNA sequence and does not involve movement of genetic elements. It is not classified as a mobile genetic element.
- **Endonuclease**: This is an enzyme that cuts DNA at specific sites. While it is important in biotechnology, it is not a mobile genetic element.
- **Variations**: This term refers to differences in traits among individuals and does not pertain to mobile genetic elements.

4. **Conclusion**: Based on the analysis, the only option that qualifies as a mobile genetic element is **Transposons**.

5. **Final Answer**: The mobile genetic element is **Transposons**.

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