Assertion: A thermostable DNA polymerase in used in PCR for repeated amplification
Reason :It remain active during high temperature induced denaturation of ds DNA

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
B. It both Assertion & Reason are True but Reason is not a correct explanation of the Assetion
C. If Assertion is True but the Reason is False
D. If both Assertion & Reason are false

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that a thermostable DNA polymerase is used in PCR (Polymerase Chain Reaction) for repeated amplification. This is true because PCR involves repeated cycles of DNA denaturation, annealing, and extension, which require a DNA polymerase that can withstand high temperatures.

2. **Understanding the Reason**: The reason provided is that the thermostable DNA polymerase remains active during high-temperature induced denaturation of double-stranded DNA. This is also true. During PCR, the DNA strands are separated (denatured) at around 94°C, and a thermostable polymerase, such as Taq polymerase, is necessary to remain functional at this temperature.

3. **Analyzing the Relationship**: The assertion and reason are both true. Additionally, the reason correctly explains why a thermostable DNA polymerase is essential in PCR. The ability of the polymerase to remain active at high temperatures allows for the repeated cycles of amplification that characterize PCR.

4. **Conclusion**: Both the assertion and the reason are true, and the reason provides a correct explanation for the assertion. Therefore, the answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

**Final Answer**: Both Assertion and Reason are true, and the Reason is the correct explanation of the Assertion.

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