A group of population splitting into two populations due to some factor, can be called two independent species only when

Options

A. They can interbreed with each other
B. They cannot interbreed with each other
C. They are not geographically isolated
D. None of these.

Answer

To determine when a group of populations that has split into two can be considered as two independent species, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Population Splitting**:
- A population can split into two due to various factors such as environmental changes, geographical barriers, or other physical separations.

2. **Defining Independent Species**:
- For two populations to be classified as independent species, they must not be able to interbreed or produce viable offspring.

3. **Interbreeding and Species Definition**:
- If two populations can interbreed, they are considered part of the same species. This means that they can produce fertile offspring together.

4. **Criteria for Independent Species**:
- The key criterion for two populations to be recognized as independent species is that they **cannot** interbreed. This means that reproductive barriers must exist between them.

5. **Conclusion**:
- Therefore, the correct answer to the question is that two populations can be called independent species only when they **cannot intervene with each other** (option B).

### Final Answer:
Two independent species can only be recognized when they **cannot intervene with each other**.

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