DNA recombinant technology uses
A . Restiction endonucleases B. DNA ligase
C. Cloning vector D. Electrophoresis

Options

A. A,B
B. B,C
C. C,D
D. A,B,C,D

Answer

To solve the question regarding which components are used in DNA recombinant technology, we will analyze each option provided:

1. **Understanding DNA Recombinant Technology**: This technology involves manipulating genetic material, specifically DNA, to create new genetic combinations. It is widely used in various fields such as medicine, agriculture, and research.

2. **Analyzing the Options**:
- **Option A: Restriction Endonucleases**: These are enzymes that cut DNA at specific sequences. They are essential for creating fragments of DNA that can be manipulated and inserted into vectors. Thus, they are indeed used in recombinant DNA technology.
- **Option B: DNA Ligase**: This enzyme is responsible for joining DNA fragments together by forming phosphodiester bonds. It is crucial for sealing the DNA fragments after they have been cut and inserted into vectors, making it a key component in recombinant DNA technology.
- **Option C: Cloning Vector**: A cloning vector is a DNA molecule used to carry foreign genetic material into a host cell. It is essential for the cloning process, allowing for the replication and expression of the inserted DNA. Therefore, it is also used in recombinant DNA technology.
- **Option D: Electrophoresis**: This is a technique used to separate macromolecules like DNA, RNA, and proteins based on size and charge. While it is not directly involved in the manipulation of DNA, it is used to analyze and visualize the results of recombinant DNA experiments.

3. **Conclusion**: Since all four options (A, B, C, and D) are utilized in various aspects of recombinant DNA technology, the correct answer is that all of them are used.

### Final Answer:
**A, B, C, and D are all used in DNA recombinant technology.**

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