A desirable change in genotype of an organism is obtained by

Options

A. DNA replication
B. protein synthesis
C. DNA technology
D. mRNA formation

Answer

To answer the question "A desirable change in genotype of an organism is obtained by," we can analyze the provided options step by step.

### Step-by-Step Solution:

1. **Understanding the Options**:
- The options given are:
- DNA replication
- Protein synthesis
- DNA technology
- mRNA formation

2. **Evaluating DNA Replication**:
- DNA replication is the process by which a cell makes a copy of its DNA. This process is essential for cell division but does not inherently change the genotype of an organism. Therefore, this option is not correct.

3. **Evaluating Protein Synthesis**:
- Protein synthesis is the process where the information in DNA is used to create proteins. This involves transcription (DNA to mRNA) and translation (mRNA to protein). While important for expressing traits, it does not change the genotype itself. Thus, this option is also not correct.

4. **Evaluating DNA Technology**:
- DNA technology, particularly recombinant DNA technology (rDNA technology), involves combining DNA from different sources. This process can create new genetic combinations that can express desirable traits. This is a method used to achieve changes in the genotype of an organism, making this option a strong candidate.

5. **Evaluating mRNA Formation**:
- mRNA formation is part of the process of protein synthesis where DNA is transcribed into messenger RNA. Like protein synthesis, this does not alter the genotype of the organism. Therefore, this option is not correct.

6. **Conclusion**:
- The only option that directly leads to a desirable change in the genotype of an organism is **DNA technology**, specifically recombinant DNA technology. This method allows for the introduction of new traits into an organism's genetic makeup.

### Final Answer:
A desirable change in genotype of an organism is obtained by **DNA technology** (specifically recombinant DNA technology).

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