Giant mouse has been produced through

Options

A. gene transfer
B. gene differentiation
C. tissue culture
D. all of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks how the giant mouse has been produced. We need to identify the method used to create this genetically modified organism.

2. **Identifying the Type of Mouse**: The giant mouse is classified as a transgenic mouse. This means that its DNA has been altered by the introduction of foreign genes.

3. **Gene Manipulation**: The production of the giant mouse involves the manipulation of its DNA. Specifically, a gene responsible for the human growth factor has been introduced into the mouse's genome.

4. **Result of Gene Introduction**: The introduction of the human growth factor gene leads to an increase in size, making the mouse larger than normal mice. This is a direct result of the genetic modification.

5. **Conclusion**: Since the giant mouse was produced through the introduction of a gene into its DNA, we conclude that the correct answer is that it has been produced through gene transfer.

6. **Final Answer**: The giant mouse has been produced through gene transfer.

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