Mark the odd one out w.r.t. the practical use of the technique of PCR :

Options

A. DNA amplification
B. Detection of mutation
C. Nucleotide sequencing
D. All of these are correct

Answer

To solve the question "Mark the odd one out w.r.t. the practical use of the technique of PCR," we need to analyze the given options and determine which one does not fit with the practical applications of PCR.

### Step-by-Step Solution:

1. **Understand PCR**: The Polymerase Chain Reaction (PCR) is a technique used to amplify DNA, creating multiple copies of a specific DNA segment. This is crucial for various applications in molecular biology.

2. **Evaluate the Options**:
- **DNA Amplification**: This is the primary function of PCR, where specific DNA sequences are amplified.
- **Detection of Mutation**: PCR can be used to identify mutations in DNA by amplifying regions of interest and analyzing them.
- **Nucleotide Sequencing**: PCR is often used to amplify DNA samples before sequencing, making it an essential step in the sequencing process.
- **All of these are correct**: This option suggests that all the previous options are valid uses of PCR.

3. **Identify the Odd One Out**:
- Since DNA amplification, detection of mutation, and nucleotide sequencing are all practical uses of PCR, the option "All of these are correct" does not represent a specific application but rather confirms that all the other options are valid. Therefore, it stands out as the odd one.

4. **Conclusion**: The correct answer is "All of these are correct," as it encompasses the validity of the other options rather than representing a distinct application.

### Final Answer:
The odd one out with respect to the practical use of the technique of PCR is **"All of these are correct."**

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