Which organism is known as Natural Genetic Engineer in plants because of its ability of gene transfer?

Options

A. Agrobacterium tumefaciens
B. E. coli
C. HaemoF hilus influenzae
D. Staphylococcus aureus

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which organism is referred to as a "Natural Genetic Engineer" in plants due to its ability to transfer genes.

2. **Identifying the Options**: The options provided are:
- Agrobacterium tumefaciens
- E. coli
- Haemophilus influenzae
- Staphylococcus aureus

3. **Recognizing Key Characteristics**: Among these options, we need to identify the organism known for its gene transfer capabilities in plants.

4. **Researching Agrobacterium tumefaciens**: Agrobacterium tumefaciens is a soil bacterium that is known for its ability to transfer a specific segment of its DNA (T-DNA) into the genome of dicot plants, causing crown gall disease.

5. **Understanding T-DNA and T.I. Plasmid**: The T-DNA is part of the Tumor Inducing (T.I.) plasmid found in Agrobacterium tumefaciens. This plasmid allows the bacterium to insert genes into the plant's DNA, effectively transforming normal plant cells into tumor cells.

6. **Conclusion**: Since Agrobacterium tumefaciens has the natural ability to transfer its T-DNA to host plants, it is referred to as a "Natural Genetic Engineer". Therefore, the correct answer is **Agrobacterium tumefaciens**.

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