PCR-technique is used in

Options

A. Production of transgenic microbes
B. Production of genetically modified food
C. Forensic investigation
D. rDNA techique

Answer

**Step-by-Step Solution:**

1. **Understand the PCR Technique:**
- PCR stands for Polymerase Chain Reaction. It is a method used to amplify small segments of DNA, making millions of copies of a specific DNA sequence.

2. **Identify the Purpose of PCR:**
- The main purpose of PCR is to amplify short DNA segments. This is particularly useful when the amount of DNA available is very small.

3. **Analyze the Options:**
- We have four options to consider regarding the application of the PCR technique:
- **Option 1:** Production of transgenic microbes
- **Option 2:** Production of genetically modified food
- **Option 3:** Forensic investigation
- **Option 4:** Recombinant DNA technique

4. **Evaluate Each Option:**
- **Option 1:** Production of transgenic microbes - This involves genetic engineering techniques, but PCR is not specifically used in this process.
- **Option 2:** Production of genetically modified food - This also falls under genetic engineering, and PCR is not a primary technique used here.
- **Option 3:** Forensic investigation - PCR is extensively used in forensic science to amplify DNA from small samples, making it possible to analyze genetic material from crime scenes.
- **Option 4:** Recombinant DNA technique - This is another genetic engineering process where PCR is not a direct requirement.

5. **Select the Correct Option:**
- Based on the evaluation, **Option 3: Forensic investigation** is the correct answer, as PCR is indeed used in this field to analyze DNA from limited samples.

**Final Answer:**
PCR technique is used in forensic investigation.

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