In recombinant DNA technology, a plasmid vector is cleaved by

Options

A. modified DNA ligase
B. a heated alkaline solution
C. the same enzyme that cleaves the donor DNA
D. the different enzyme than that cleaves the donor DNA.

Explanation

To answer the question about how a plasmid vector is cleaved in recombinant DNA technology, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Role of Plasmid Vectors**:
- Plasmid vectors are small, circular DNA molecules used to transfer genetic material into a host cell. They are essential tools in recombinant DNA technology.

2. **Cleavage of Plasmid Vectors**:
- To insert foreign DNA into a plasmid vector, the vector must first be opened or cleaved. This is typically done using specific enzymes.

3. **Identifying the Enzymes**:
- The enzymes that are commonly used to cleave plasmid vectors are called restriction endonucleases (or restriction enzymes). These enzymes cut DNA at specific sequences.

4. **Analyzing the Options**:
- **A. Modified DNA ligase**: This enzyme is used to join DNA fragments together, not to cleave them.
- **B. Heated alkaline solution**: This does not cleave DNA; it is generally used for denaturing DNA.
- **C. The same enzyme that cleaves the donor DNA**: This is a plausible option since the same restriction enzyme can be used to cut both the plasmid and the donor DNA to create compatible ends.
- **D. Different enzyme that cleaves the donor DNA**: This option is also plausible, as different restriction enzymes can be used to cut the donor DNA and the plasmid, as long as they create compatible ends.

5. **Conclusion**:
- The most accurate answer is **C. The same enzyme that cleaves the donor DNA**, as it is common practice to use the same restriction enzyme for both the plasmid and the donor DNA to ensure that the ends are compatible for ligation.

### Final Answer:
**C. The same enzyme that cleaves the donor DNA.**