To which of the following techniques would you associ- ate the phenomenon of insertional inactivation?

Options

A. Southern blotting
B. Northern blotting
C. Selection of recombinants
D. Microprojection

Answer

To determine which technique is associated with the phenomenon of insertional inactivation, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Insertional Inactivation**:
- Insertional inactivation is a phenomenon that occurs during recombinant DNA technology. It involves the insertion of foreign DNA into a gene, which disrupts the gene's function, rendering it non-functional or inactive.

2. **Identify the Techniques Listed**:
- The techniques provided in the question are:
- Southern blotting
- Northern blotting
- Selection of recombinant DNA
- Micro-projection

3. **Analyze Each Technique**:
- **Southern Blotting**:
- This technique is used to detect specific DNA sequences. It does not involve the insertion of DNA into a gene and is not related to insertional inactivation.
- **Northern Blotting**:
- This technique is used to study gene expression by detecting RNA. Similar to Southern blotting, it does not involve insertional inactivation.
- **Selection of Recombinant DNA**:
- This technique is directly related to recombinant DNA technology. It involves selecting bacteria that have taken up recombinant plasmids, which may include the phenomenon of insertional inactivation as it involves the insertion of foreign DNA into a gene, disrupting its function.
- **Micro-projection**:
- This technique involves the physical delivery of DNA into cells but does not specifically relate to insertional inactivation.

4. **Conclusion**:
- Based on the analysis, the technique that is associated with the phenomenon of insertional inactivation is the **Selection of Recombinant DNA**.

### Final Answer:
- The correct answer is **Selection of Recombinant DNA**.