In which of the following techniques, the mRNA is prevented from undergoing translation due to presence of a complementary segment?

Options

A. Gene gun technology
B. DNA interference
C. RNA interference
D. Gene deletion

Answer

To solve the question "In which of the following techniques, the mRNA is prevented from undergoing translation due to the presence of a complementary segment?" we will analyze each of the given options step by step.

### Step-by-Step Solution:

1. **Understanding the Question**:
- The question asks about a technique that prevents mRNA from being translated into protein. This involves a mechanism where a complementary segment binds to the mRNA, inhibiting its function.

2. **Analyzing the Options**:
- **Option 1: Gene Gun Technology**:
- This method is used to introduce foreign DNA or RNA into cells using a projectile method. It does not prevent mRNA translation; rather, it facilitates the introduction of genetic material into cells.
- **Option 2: DNA Interference**:
- This term is somewhat misleading as it suggests a process involving DNA. While DNA can influence RNA, the term is not commonly used to describe a technique that directly prevents mRNA translation.
- **Option 3: RNA Interference (RNAi)**:
- This is a well-established biological process where small RNA molecules (like siRNA or miRNA) bind to complementary sequences on mRNA, leading to its degradation or inhibition of translation. This directly addresses the question.
- **Option 4: Gene Deletion**:
- This refers to the removal of a gene from the genome. While it may affect the production of mRNA, it does not involve a mechanism that directly prevents existing mRNA from being translated.

3. **Conclusion**:
- Based on the analysis, the correct answer is **Option 3: RNA Interference**. This technique specifically involves the action of small RNA molecules that bind to mRNA and prevent its translation.

### Final Answer:
**RNA Interference (Option 3)** is the technique in which mRNA is prevented from undergoing translation due to the presence of a complementary segment.

---