Which of the following is CORRECTLY matched ?

Options

A. Agrobacterium tumefaciens - tumor
B. Thermus aquaticus - Bt - gene
C. pBR 322 - enzyme
D. Ligase - molecular scissor

Answer

To determine which of the following options is correctly matched, let's analyze each option step by step:

### Step 1: Analyze Option A - Agrobacterium Tumefaciens
- **Agrobacterium Tumefaciens** is a bacterium known for causing tumors in plants, specifically crown gall disease.
- This option is correctly matched because Agrobacterium is indeed associated with tumor formation in plants.

### Step 2: Analyze Option B - Thermus Aquaticus
- **Thermus Aquaticus** is a thermophilic bacterium known for its heat-stable DNA polymerase, often referred to as Taq polymerase, which is widely used in PCR (Polymerase Chain Reaction).
- The option incorrectly states "bt gene" which is not associated with Thermus Aquaticus. Therefore, this option is incorrect.

### Step 3: Analyze Option C - PBR 322
- **PBR 322** is a plasmid vector used in molecular cloning, particularly in E. coli. It contains genes for antibiotic resistance and is used to facilitate the cloning of DNA.
- The option incorrectly states "enzyme," which is misleading. PBR 322 is not an enzyme but a vector. Thus, this option is incorrect.

### Step 4: Analyze Option D - Ligase
- **Ligase** is an enzyme that joins DNA fragments together, particularly during DNA replication and repair. However, it is not classified as a "molecular scissors."
- The term "molecular scissors" typically refers to restriction enzymes, which cut DNA at specific sequences. Therefore, this option is also incorrect.

### Conclusion
After analyzing all the options, we find that:
- Option A (Agrobacterium Tumefaciens - tumor) is correctly matched.
- Options B, C, and D are incorrect.

Thus, the correct answer is **Option A**.

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