Which of the following will form a new species?

Options

A. interbreeding
B. variations
C. differential reproduction
D. none of the above

Answer

To determine which of the following options will form a new species, we need to analyze each option carefully:

1. **Interbreeding**:
- Interbreeding refers to the mating of individuals within the same species. While interbreeding can lead to genetic variation within a species, it does not typically result in the formation of a new species. Therefore, this option is incorrect.

2. **Variations**:
- Variations arise from genetic differences among individuals, often due to mutations and sexual reproduction. While variations are essential for evolution, they alone do not lead to the formation of a new species. They must be acted upon by natural selection or other mechanisms. Thus, this option is also incorrect.

3. **Differential Reproduction**:
- Differential reproduction refers to the varying ability of individuals to reproduce based on their adaptations to the environment. Those individuals that are better adapted tend to reproduce more successfully, leading to the evolution of new traits over time. This process can eventually lead to the formation of a new species. Therefore, this option is correct.

4. **None of the above**:
- Since we have identified that differential reproduction can lead to the formation of a new species, this option is not applicable.

### Conclusion:
The correct answer is **Option 3: Differential reproduction**.

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