Transgenic rats, rabbits, pigs, sheep, cows and fish have been produced, Almost over 95 percent of all existing transgenic animals are :

Options

A. sheep
B. fish
C. mice
D. pigs

Answer

**Step-by-Step Solution:**

1. **Understanding Transgenic Animals**: Transgenic animals are those whose genomes have been altered through genetic engineering. This alteration is typically achieved using recombinant DNA technology (rDNA technology).

2. **Identifying Common Transgenic Animals**: Various species have been genetically modified, including rats, rabbits, pigs, sheep, cows, and fish. However, the question focuses on the percentage of transgenic animals produced.

3. **Analyzing the Data**: It is noted that over 95% of all existing transgenic animals are of a specific type.

4. **Identifying the Most Common Transgenic Animal**: Among the various transgenic animals produced, mice are the most commonly used. They account for a significant majority of transgenic animals due to their small size, short life cycle, and ease of genetic manipulation.

5. **Conclusion**: Therefore, the answer to the question is that over 95% of all existing transgenic animals are mice.

**Final Answer**: Mice

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