Assertion : Ti plasmid obtained from Agrobacterium tumefaciens is effectively used as a vector for gene transfer in plant cells.
Reason : The part of Ti plasmid transferred into the DNA of plant cells is called as T-DNA.

Options

A. Both Assertion and Reason are correct and reason is the correct explanation for assertion
B. Both Assertion and Reason are correct but reason is not the correct explanation for assertion
C. Assertion is correct but reason is incorrect
D. Both assertion and reason are incorrect

Explanation

To analyze the assertion and reason provided in the question, we will break down the information step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Ti plasmid obtained from Agrobacterium tumefaciens is effectively used as a vector for gene transfer in plant cells."
- This is true because Ti plasmids are naturally occurring plasmids in Agrobacterium tumefaciens that can transfer genetic material into plant cells.

2. **Understanding the Reason**:
- The reason given is "The part of Ti plasmid transferred into the DNA of plant cells is called T-DNA."
- This is also true. T-DNA (Transfer DNA) is the segment of the Ti plasmid that is integrated into the plant genome during the process of transformation.

3. **Evaluating the Relationship**:
- While both the assertion and reason are correct, we need to assess whether the reason provides a correct explanation for the assertion.
- The assertion discusses the use of Ti plasmid as a vector for gene transfer, while the reason explains what part of the Ti plasmid is transferred (T-DNA).
- The reason does not directly explain why the Ti plasmid is effective as a vector; it merely states a fact about the T-DNA.

4. **Conclusion**:
- Both the assertion and reason are correct statements, but the reason does not adequately explain the assertion. Therefore, the correct answer to the question is that both statements are true, but the reason is not the correct explanation for the assertion.

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

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