The vector for T-DNA is

Options

A. Thermus aquaticus
B. Salmonella tyhimurium
C. Agrobacterium tumefaciens
D. Bacillus thuringiensis

Answer

**Step-by-Step Solution:**

1. **Understanding T-DNA**: T-DNA (Transfer DNA) is a segment of DNA that is transferred from Agrobacterium tumefaciens to the plant cell during the infection process. It is crucial for plant genetic engineering.

2. **Identifying the Options**: The question provides four options:
- A) Thermosacquaticus
- B) Salmonella typhimurium
- C) Agrobacterium tumefaciens
- D) Bacillus thuringiensis

3. **Analyzing Option A - Thermosacquaticus**: This is a thermophilic bacterium that can withstand high temperatures. It is not involved in T-DNA transfer, making this option incorrect.

4. **Analyzing Option B - Salmonella typhimurium**: This is a pathogenic bacterium known for causing typhoid fever. It does not play a role in T-DNA transfer, so this option is also incorrect.

5. **Analyzing Option C - Agrobacterium tumefaciens**: This bacterium is known for its ability to transfer T-DNA to plant cells, causing crown gall disease. It is widely used as a vector in plant genetic engineering, making this option correct.

6. **Analyzing Option D - Bacillus thuringiensis**: This bacterium is known for producing insecticidal proteins and is used in the development of genetically modified crops like BT cotton. However, it is not used as a vector for T-DNA transfer, making this option incorrect.

7. **Conclusion**: After analyzing all the options, the correct answer is **C) Agrobacterium tumefaciens**, as it is the vector used for T-DNA transfer in plant genetic engineering.

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