99% of genes of this animal are direct counter parts of the humans

Options

A. Rana tigrina
B. Mus musculus
C. Struthio camelus
D. Drosophila melanogaster

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which animal has 99% of its genes that are direct counterparts to humans. This indicates a close genetic relationship between humans and the animal in question.

2. **Analyzing the Options**: The options provided are:
- Rana Tigrina (a frog species)
- Mus musculus (a species of mouse/rat)
- Struthio camelus (the common ostrich)
- Drosophila melanogaster (a fruit fly)

3. **Identifying Genetic Similarities**: To answer the question, we need to consider which of these animals is known for having a high percentage of genetic similarity with humans. Research indicates that mice (Mus musculus) share a significant amount of genetic material with humans, often cited as around 99%.

4. **Eliminating Other Options**:
- **Rana Tigrina**: Frogs do not have such a high genetic similarity with humans.
- **Struthio camelus**: Ostriches also do not share 99% of their genes with humans.
- **Drosophila melanogaster**: Fruit flies are model organisms in genetics but have a much lower percentage of genetic similarity to humans compared to mice.

5. **Conclusion**: Based on the analysis, the animal that has 99% of its genes as direct counterparts to humans is **Mus musculus** (the mouse/rat). Therefore, the correct answer is option **Mus musculus**.

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