A : Sigma factor of RNA polymerase recognizes the start single region in prokaryotes.
R: Promotor region lies at 5' of template strand.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark
B. If both Assertion & Reason are true and the reason is not the correct explanation of the assertion , then mark
C. If Assertion is ture statement but Reason is false, then mark.
D. If both Assertion and Reason are false statements, then mark.

Answer

To solve the assertion and reason question, we need to analyze both statements and determine their correctness.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states: "Sigma factor of RNA polymerase recognizes the start single region in prokaryotes."
- The sigma factor is a protein that associates with RNA polymerase to facilitate the initiation of transcription in prokaryotes. It helps the RNA polymerase to bind to the promoter region of the DNA, which is crucial for starting the transcription process.

2. **Understanding the Reason**:
- The reason states: "Promoter region lies at 5' of template strand."
- The promoter region is indeed located at the 5' end of the template strand in DNA. This is where RNA polymerase, along with the sigma factor, binds to initiate transcription. The promoter is essential for the correct positioning of RNA polymerase to start synthesizing RNA.

3. **Evaluating the Statements**:
- Both the assertion and the reason are correct. The sigma factor does recognize the start signal (the promoter region) in prokaryotes, and the promoter region is located at the 5' end of the template strand.

4. **Conclusion**:
- Since both statements are true, we conclude that the assertion and reason are both correct and related to each other.

### Final Answer:
Both the assertion (A) and the reason (R) are correct. Therefore, the correct answer is that both statements are true, and the reason correctly explains the assertion.

---