Transfer of any gene into a completely different organism can be done through

Options

A. Genetic engineering
B. Tissue culture
C. Transformation
D. RNA interference

Answer

To answer the question, "Transfer of any gene into a completely different organism can be done through," we need to analyze the options provided and understand the relevant biological processes involved.

### Step-by-Step Solution:

1. **Understanding Gene Transfer**: The transfer of a gene from one organism to another involves introducing foreign DNA into the target organism's genome. This is a fundamental concept in biotechnology.

2. **Analyzing the Options**:
- **Genetic Engineering**: This is a broad term that encompasses various techniques used to manipulate an organism's DNA. It includes the insertion of foreign genes into an organism, making it a strong candidate for the answer.
- **Tissue Culture**: This refers to the growth of cells in a controlled environment outside of their natural habitat. While it is important for plant propagation and research, it does not involve the direct transfer of genes between different organisms.
- **Transformation**: This is a specific method of genetic engineering where a cell takes up foreign DNA from its environment. However, it is not a standalone process that applies universally to all organisms.
- **RNA Interference**: This is a biological process in which RNA molecules inhibit gene expression. It does not involve the transfer of genes between organisms.

3. **Conclusion**: Based on the analysis, the most appropriate method for transferring a gene into a completely different organism is **Genetic Engineering**. This process allows for the manipulation and introduction of foreign DNA into an organism's genome.

### Final Answer:
The transfer of any gene into a completely different organism can be done through **Genetic Engineering**.

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