Which of the flowing has the ability to transform normal cell into cancerous cell in animal

Options

A. Agrobacterium tumifaciens
B. Retroviruses
C. DNA - viruses
D. DNA - viruses

Answer

To answer the question "Which of the following has the ability to transform normal cells into cancerous cells in animals?", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The question provides multiple options, including Agrobacterium tumefaciens and retrovirus. We need to analyze these options to determine which one can transform normal cells into cancerous cells specifically in animals.

2. **Understand Agrobacterium tumefaciens**:
- Agrobacterium tumefaciens is a bacterium that primarily affects dicot plants.
- It transfers a piece of DNA known as T-DNA into plant cells, causing them to become cancerous (specifically, it induces crown gall tumors).
- However, it does not have the ability to transform normal cells into cancerous cells in animals.

3. **Understand Retrovirus**:
- Retroviruses are a type of virus that can infect animal cells.
- They have the ability to insert their RNA genome into the DNA of the host cell using an enzyme called reverse transcriptase.
- This process can lead to mutations and changes in the host cell's genome, which can result in the transformation of normal cells into cancerous cells.

4. **Conclusion**: Based on the analysis, the correct answer is the retrovirus, as it is capable of transforming normal cells into cancerous cells in animals.

### Final Answer:
The ability to transform normal cells into cancerous cells in animals is attributed to **retrovirus**.

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