The techniques of genetic engineering include

Options

A. Creation of recombinant DNA
B. Gene cloning
C. Gene transfer
D. All of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding Genetic Engineering**: Genetic engineering, also known as genetic modification, involves the manipulation of an organism's genes. This process allows scientists to alter the genetic makeup of organisms.

2. **Direct Manipulation of Genes**: In genetic engineering, there is a direct manipulation of genes. This means that specific genes can be added, removed, or altered within an organism’s DNA.

3. **Biotechnology Tools**: The tools used in genetic engineering are referred to as biotechnology tools. These tools facilitate the manipulation of genetic material.

4. **Key Techniques in Genetic Engineering**:
- **Creation of Recombinant DNA**: One of the primary techniques is the creation of recombinant DNA, which involves combining DNA from different sources.
- **Gene Cloning**: Another important technique is gene cloning, where specific genes are copied to produce multiple identical copies.
- **Gene Transfer**: Gene transfer is also a significant technique, where genes are transferred from one organism to another, allowing for the introduction of new traits.

5. **Conclusion**: All the mentioned techniques—creation of recombinant DNA, gene cloning, and gene transfer—are integral parts of genetic engineering. Therefore, the correct answer is that all these techniques are included in genetic engineering.

**Final Answer**: The techniques of genetic engineering include the creation of recombinant DNA, gene cloning, and gene transfer.

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