The percentage of base sequences that are nearly identical among all humans is

Options

A. `90%`
B. `80%`
C. `99.9%`
D. `89.9%`

Answer

To solve the question regarding the percentage of base sequences that are nearly identical among all humans, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Base Sequences**:
- DNA is composed of four types of nucleotide bases: Adenine (A), Cytosine (C), Guanine (G), and Thymine (T).
- These bases pair specifically: A pairs with T, and C pairs with G.

2. **Identifying Similarity Among Humans**:
- When we talk about the base sequences in the DNA of humans, we are referring to the order of these nucleotide bases.
- Research has shown that the genetic makeup of humans is remarkably similar.

3. **Percentage of Identical Base Sequences**:
- It has been established that approximately 99.9% of the base sequences in the DNA of all humans are identical.
- This means that only a small fraction (0.1%) of the base sequences varies among individuals, which accounts for genetic diversity.

4. **Conclusion**:
- Therefore, the answer to the question is that the percentage of base sequences that are nearly identical among all humans is **99.9%**.

### Final Answer:
- The percentage of base sequences that are nearly identical among all humans is **99.9%**.

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