The transgenic animals are those which have

Options

A. foreign DNA in some of their cells
B. foreign DNA in all of their cells
C. foreign RNA in all of their cells
D. both (1) and (3)

Answer

**Step-by-Step Solution:**

1. **Understanding Transgenic Animals**:
- Transgenic animals are those that have had their genetic material altered through the introduction of foreign DNA. This process is part of genetic engineering.

2. **Foreign DNA in Cells**:
- The key characteristic of transgenic animals is that they contain foreign DNA. This DNA can be present in some cells or all cells of the animal.

3. **Analyzing the Options**:
- The question provides options regarding the presence of foreign DNA and RNA in the cells of transgenic animals.
- Option 1 states that there is foreign DNA in some of their cells.
- Option 2 states that there is foreign DNA in all of their cells.
- Option 3 states that there is foreign RNA in all of their cells.
- Option 4 states that both options 1 and 3 are correct.

4. **Evaluating Each Statement**:
- **Option 1**: Correct. Transgenic animals can have foreign DNA inserted into some of their cells.
- **Option 2**: Incorrect. It is not necessary for all cells to contain foreign DNA; this could lead to complications and is not typical for transgenic animals.
- **Option 3**: Incorrect. The presence of foreign RNA in all cells is not a standard characteristic of transgenic animals.
- **Option 4**: Incorrect, as it claims both options 1 and 3 are correct, but option 3 is incorrect.

5. **Conclusion**:
- The correct answer is that transgenic animals have foreign DNA in some of their cells (Option 1).

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

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