Assertion (A) : EcoRI is restriction endonuclease enzyme. Reason (R): Exonuclease removes nucleotides from the ends of DNA.

Options

A. Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
B. Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
C. Assertion (A) is true but reason (R) is false.
D. Assertion (A) is false but reason (R) is true.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "EcoRI is a restriction endonuclease enzyme."
- EcoRI is indeed a well-known restriction enzyme that cuts DNA at specific sites. It is classified as an endonuclease because it cleaves the phosphodiester bonds within the DNA molecule.

2. **Understanding the Reason:**
- The reason states that "Exonuclease removes nucleotides from the ends of DNA."
- Exonucleases are enzymes that remove nucleotide units from the ends of a DNA molecule, either from the 5' end or the 3' end. This statement is also correct.

3. **Evaluating the Relationship:**
- Both the assertion and the reason are true statements. However, the reason does not directly explain the assertion. The assertion is about EcoRI being a restriction endonuclease, while the reason discusses the function of exonucleases, which is unrelated to the function of EcoRI.

4. **Conclusion:**
- Since both the assertion and reason are true, but the reason does not explain the assertion, the correct answer is: "Both assertion and reason are true, but the reason is not the correct explanation for the assertion."

**Final Answer:**
Both assertion and reason are true, but the reason is not the correct explanation for the assertion.

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