Which one of the following is correctly matched ?

Options

A. Agrobacterium tumifaciens - tumor
B. Thermus aquatics - Bt-gene .
C. pBR322 - enzymes.
D. Ligase - Molecule scissors.

Answer

To determine which of the following options is correctly matched, we will analyze each option one by one.

### Step-by-Step Solution:

1. **Option 1: Agrobacterium Tumefaciens - Tumor**
- Agrobacterium Tumefaciens is a soil bacterium known for causing crown gall disease in plants, which results in tumor formation. This bacterium contains a plasmid known as the T.I. (tumor-inducing) plasmid that facilitates the tumor formation in the host plant. Therefore, this option is correctly matched.

2. **Option 2: Thermus Aquaticus - Bt Gene**
- Thermus Aquaticus is a bacterium that is known for its heat-resistant enzyme, Taq polymerase, which is used in PCR (Polymerase Chain Reaction) processes. The Bt gene, on the other hand, is derived from Bacillus thuringiensis, a different bacterium, which is used in genetically modified crops like Bt cotton. Hence, this option is incorrectly matched.

3. **Option 3: PBR322 - Restriction Enzymes**
- PBR322 is a plasmid used in cloning, but it is not a restriction enzyme itself. Instead, it contains genes that confer antibiotic resistance and is used as a vector in molecular cloning. Restriction enzymes are separate entities that cut DNA at specific sequences. Therefore, this option is also incorrectly matched.

4. **Option 4: Ligase - Molecular Scissors**
- DNA ligase is an enzyme that joins DNA fragments together, whereas restriction enzymes are referred to as "molecular scissors" because they cut DNA at specific sites. Thus, calling ligase "molecular scissors" is incorrect, making this option wrong as well.

### Conclusion:
The only correctly matched option is **Option 1: Agrobacterium Tumefaciens - Tumor**.

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