Assertion :- Inhibition of transcription is the only method of regulation of gene expression in all organisms.
Reason : Transcription is the first step of gene expression.

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:** The assertion states that "Inhibition of transcription is the only method of regulation of gene expression in all organisms." This implies that the only way to regulate gene expression is by stopping transcription.

2. **Evaluating the Assertion:** This statement is incorrect. While inhibition of transcription is indeed one method of regulating gene expression, it is not the only method. There are multiple levels and mechanisms of gene regulation, especially in eukaryotes.

3. **Understanding the Reason:** The reason states that "Transcription is the first step of gene expression." This suggests that transcription is the initial process in the pathway of gene expression.

4. **Evaluating the Reason:** This statement is partially true. Transcription is indeed a crucial step in gene expression, but it is not the very first step. The first step involves the DNA itself, where the information is stored and accessed before transcription occurs.

5. **Conclusion:** Both the assertion and the reason are false. The assertion is incorrect because there are multiple methods of gene regulation, and the reason is misleading because it does not accurately represent the sequence of events in gene expression.

6. **Final Answer:** Therefore, the correct conclusion is that both the assertion and the reason are false.

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