Genetic engineering has been successfully used for producing

Options

A. transgenic mice for testing safety of polio vaccine before use in humans
B. transgenic cow-Rosie which produces high fat milk for making ghee
C. animals like bulbs for farm work as they have super power
D. all of these

Explanation

**Step-by-Step Solution:**

1. **Understand Genetic Engineering**: Genetic engineering is a biotechnological process that involves altering the genetic material of an organism to achieve desired traits or characteristics.

2. **Evaluate the Options**: We need to analyze each option provided in the question to determine which one correctly represents a successful application of genetic engineering.

3. **Option 1 - Transgenic Mice**: This option states that transgenic mice have been created to test the safety of the polio vaccine before it is administered to humans. This is a valid application of genetic engineering, as transgenic mice can be used as models for human diseases and treatments.

4. **Option 2 - Transgenic Cow (Rosie)**: This option mentions Rosie, a transgenic cow that produces high-fat milk suitable for making ghee. This is also a successful application of genetic engineering, as it involves modifying the cow's genetics to enhance milk production.

5. **Option 3 - Animals for Farm Work**: This option suggests that birds have been genetically engineered to possess "super powers" for farm work. However, this is not a recognized application of genetic engineering and seems more fictional than factual.

6. **Option 4 - All of the Above**: This option implies that all previous options are correct applications of genetic engineering. However, since option 3 is questionable, this option cannot be correct.

7. **Conclusion**: After evaluating all the options, the most accurate answer is option 1, which highlights the use of transgenic mice for testing the safety of the polio vaccine.

**Final Answer**: Option 1 - Transgenic mice for testing safety of polio vaccine before use in humans.

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