Polymerase chain reaction is concerned with :

Options

A. DNA amplification
B. DNA repairing
C. DNA proof reading
D. DNA replication

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what the Polymerase Chain Reaction (PCR) is primarily concerned with. The options provided are DNA amplification, DNA repairing, DNA proofreading, and DNA replication.

2. **Defining PCR**: Polymerase Chain Reaction (PCR) is a laboratory technique used to make multiple copies of a specific DNA segment. It is essential for amplifying small amounts of DNA for various analyses.

3. **Analyzing the Options**:
- **DNA Amplification**: This is the process of increasing the number of copies of a specific DNA sequence. PCR is specifically designed for this purpose.
- **DNA Repairing**: This refers to the processes that correct damage to DNA. It is not the primary function of PCR.
- **DNA Proofreading**: This is a mechanism that ensures the accuracy of DNA replication by correcting errors. While it is important in DNA synthesis, it is not what PCR focuses on.
- **DNA Replication**: This is the process by which a cell duplicates its DNA before cell division. PCR mimics this process but is specifically aimed at amplifying DNA rather than replicating it in a cellular context.

4. **Identifying the Correct Option**: Given the definitions and purposes of each option, the correct answer is **DNA amplification**. PCR is fundamentally about amplifying specific DNA sequences.

5. **Conclusion**: Therefore, Polymerase Chain Reaction is primarily concerned with DNA amplification.

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