The transgenic animals are those which have:

Options

A. Foreign RNA in all its cells
B. Foreign DNA is some of its cells
C. Foreign DNA in all of its cells
D. Both (a) & (b)

Answer

**Step-by-Step Solution:**

1. **Understanding Transgenic Animals**: Transgenic animals are those that have been genetically modified to contain a gene or genes which have been artificially inserted instead of the animal acquiring them through reproduction.

2. **Identifying the Genetic Material**: The question asks what type of genetic material is present in transgenic animals. The options include:
- Foreign RNA in itself
- Foreign DNA in some of its cells
- Foreign DNA in all of its cells
- Both A and B

3. **Genetic Engineering Process**: In the process of creating transgenic animals, a desired gene (foreign DNA) is inserted into the genome of the animal. This is done using techniques of genetic engineering.

4. **Germ Line Incorporation**: The foreign DNA is usually incorporated into the germ line of the animal, meaning that it will be present in all of its cells, including the reproductive cells. Therefore, when the animal reproduces, the offspring will inherit this foreign DNA.

5. **Conclusion**: Since the foreign DNA is present in all cells of the transgenic animal, the correct answer to the question is "foreign DNA in all of its cells."

**Final Answer**: Transgenic animals are those which have foreign DNA in all of its cells.

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