Assertion : Unless one cuts the vector and the foreign/source DNA with the same restriction enzymes, the recombinant vector molecule cannot be created
Reason: When cut by the same restriction enzyme, the resultant DNA fragments have the same kind of sticky ends and these can be joined together (end to end) using DNA ligases

Options

A. If both assertion and reason are true and the reason is the correct explanation of the assertion
B. If both assertion and reason are true but reason is not the correct explanation of the assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that for recombinant DNA to be created, both the vector and the foreign DNA must be cut using the same restriction enzyme. This is because the ends of the DNA fragments need to be compatible for ligation.

2. **Understanding the Reason**: The reason provided explains that when both the vector and the foreign DNA are cut with the same restriction enzyme, they produce DNA fragments with identical sticky ends. These sticky ends are crucial for the ligation process, as they allow the fragments to bond together.

3. **Linking Assertion and Reason**: The assertion is correct because if different restriction enzymes are used, the resulting DNA fragments will have different ends and will not be able to join together. The reason correctly explains why the assertion is true, as it describes the necessity of having compatible sticky ends for successful ligation.

4. **Conclusion**: Both the assertion and the reason are true, and the reason accurately explains the assertion. Therefore, the correct 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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