The transgenic animals are those which have

Options

A. foreign RNA in all its cells
B. foreign DNA in some of its cells
C. foreign DNA in all its cells
D. both (a) and (c)

Explanation

**Step-by-Step Solution:**

1. **Understanding Transgenic Animals**: Transgenic animals are those that have had foreign genes inserted into their genome. This process involves the introduction of novel DNA sequences into the animal's cells.

2. **Mechanism of Creation**: The most common method for creating transgenic animals is through the injection of cloned DNA into a fertilized egg. This fertilized egg then undergoes mitotic division, leading to the development of a complete organism.

3. **Presence of Foreign DNA**: Once the fertilized egg develops into an organism, all the cells of that organism will carry the introduced foreign DNA. Therefore, transgenic animals have foreign DNA present in all of their cells.

4. **Evaluating Options**:
- Option 1: Foreign RNA in all its cells - Incorrect, as transgenic animals are defined by DNA, not RNA.
- Option 2: Foreign DNA in some of its cells - Incorrect, as transgenic animals have foreign DNA in all cells.
- Option 3: Foreign DNA in all its cells - Correct, as explained above.
- Option 4: Both A and C - Incorrect, since A is not true.

5. **Conclusion**: Based on the above reasoning, the correct answer is that transgenic animals have foreign DNA in all of their cells.

**Final Answer**: Transgenic animals are those which have foreign DNA in all its cells (Option 3).

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