In which technique do we use Taq polymerase and why ?

Explanation

### Step-by-Step Solution:

1. **Identify the Technique**: The technique in which Taq polymerase is used is called the Polymerase Chain Reaction (PCR).

2. **Understand PCR**: PCR is a molecular biology technique used to amplify specific DNA sequences, producing multiple copies of a particular segment of DNA.

3. **Role of Taq Polymerase**: Taq polymerase is a type of enzyme that synthesizes new DNA strands by adding nucleotides to a DNA template during the PCR process.

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