Selectable markers used in RDT because :-

Options

A. Selection of marker gene
B. Selection of vector
C. Selection of transformants and eliminating non-transformants
D. Selection of transforamnts and aliminatingtransformants

Answer

### Step-by-Step Solution:

1. **Understanding Recombinant DNA Technology (RDT)**:
- RDT is a method used in genetic engineering where DNA from different sources is combined to create new genetic combinations. This technology is essential for various applications in biotechnology, including gene cloning, gene therapy, and the development of genetically modified organisms (GMOs).

2. **Role of Selectable Markers**:
- Selectable markers are genes that are introduced into a vector (like a plasmid) along with the gene of interest. These markers allow for the identification of cells that have successfully taken up the recombinant DNA.

3. **Function of Selectable Markers**:
- The primary function of selectable markers is to enable the selection of transformant cells (cells that have successfully incorporated the plasmid with the gene of interest) while eliminating non-transformant cells (cells that did not take up the plasmid).

4. **Examples of Selectable Markers**:
- Common examples of selectable markers include antibiotic resistance genes, such as the ampicillin resistance gene. Cells that have taken up the plasmid will be resistant to the antibiotic, allowing researchers to easily identify and select these transformant cells by growing them in the presence of the antibiotic.

5. **Analyzing the Options**:
- The options provided in the question are:
- A) Selectable of marker gene
- B) Selection of vector
- C) Selection of transformant and eliminating non-transformant
- D) Selection of transformant and elimination of transformant
- Upon analyzing these options, option C is correct because it accurately describes the role of selectable markers in selecting transformant cells and eliminating non-transformant cells.

### Conclusion:
- The correct answer is **C) Selection of transformant and eliminating non-transformant**. This option correctly reflects the function of selectable markers in recombinant DNA technology.

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