Name the common vectros used to deliver desriable genes into plants and animals respectively .
I. Ti -Plasmid II. Retrovirus
III . F - Plasmid `" "` IV . Bacteriophage .

Options

A. I - II
B. II - III
C. III - I V
D. I - IV

Answer

To answer the question regarding the common vectors used to deliver desirable genes into plants and animals, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Vectors**: Vectors are DNA molecules that carry foreign genetic material into another cell. They are essential tools in biotechnology for gene transfer.

2. **Identifying Vectors for Plants**:
- **Ti-Plasmid**: This is derived from the bacterium *Agrobacterium tumefaciens*, which is known for inducing tumors in plants. By modifying the Ti-plasmid, scientists can insert desirable genes and use it to transfer these genes into plant cells. Thus, Ti-plasmid is a common vector for gene delivery in plants.

3. **Identifying Vectors for Animals**:
- **Retrovirus**: Retroviruses, such as the HIV virus, can integrate their genetic material into the host cell's DNA. This property makes retroviruses suitable vectors for delivering genes into animal cells, as they can effectively insert the desired gene into the genome of the target cells.

4. **Evaluating Other Options**:
- **F-Plasmid**: This plasmid is involved in bacterial conjugation and is not used for gene delivery in plants or animals.
- **Bacteriophage**: These are viruses that specifically infect bacteria and cannot be used to deliver genes into plant or animal cells.

5. **Conclusion**: Based on the analysis, the common vectors used to deliver desirable genes into plants and animals are:
- **I. Ti-Plasmid** for plants
- **II. Retrovirus** for animals

### Final Answer:
The correct vectors are:
- **I. Ti-Plasmid** (for plants)
- **II. Retrovirus** (for animals)