The techniques of genetic engineering include

Options

A. Creation of r-DNA
B. Use of gene cloning
C. Gene transfer
D. All

Answer

**Step-by-Step Solution:**

1. **Understanding Genetic Engineering**: Genetic engineering refers to the manipulation of an organism's genes using biotechnology. It involves altering the genetic material to achieve desired traits or characteristics.

2. **Identifying Techniques**: The question asks about the techniques involved in genetic engineering. The options provided are:
- A) Creation of recombinant DNA (rDNA)
- B) Use of gene cloning
- C) Gene transfer
- D) All of the above

3. **Analyzing Each Option**:
- **Option A**: Creation of recombinant DNA (rDNA) is a fundamental technique in genetic engineering. It involves combining DNA from different sources.
- **Option B**: Gene cloning is another essential technique where specific genes are copied to produce multiple identical copies.
- **Option C**: Gene transfer is the process of introducing new genetic material into a host organism, which is crucial for expressing the desired traits.

4. **Conclusion**: Since all the mentioned techniques (A, B, and C) are integral parts of genetic engineering, the correct answer is option D, which states "all of the above."

5. **Final Answer**: The techniques of genetic engineering include all of the following: creation of recombinant DNA, use of gene cloning, and gene transfer. Therefore, the correct answer is option D.

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