According of Darwin, the organic evolution is due to

Options

A. Interspecific competition
B. Competition within closely related species
C. Reduced feeding efficiency in one species due to the pressence of interfering species
D. Intraspecific competition.

Answer

### Step-by-Step Solution:

1. **Understanding Organic Evolution**:
- Organic evolution refers to the changes that occur in living organisms over time. This includes the evolution of species of plants and animals.

2. **Identifying Darwin's Contribution**:
- Charles Darwin is known for his significant contributions to the theory of evolution, particularly through the concept of natural selection.

3. **Analyzing the Options**:
- The question asks for the reason behind organic evolution according to Darwin. We need to evaluate the given options.

4. **Evaluating the First Option (Interspecific Competition)**:
- Interspecific competition refers to competition between different species for resources such as food and shelter. According to Darwin, this competition can lead to the survival of the fittest, where the more adaptable species thrive and reproduce, leading to evolution.

5. **Evaluating the Second Option (Competition within Closely Related Species)**:
- This option is incorrect because competition among closely related species can lead to resource compromise, which does not necessarily promote evolution.

6. **Evaluating the Third Option (Reduced Feeding Efficiency due to Interfering Species)**:
- This option is also incorrect. Reduced feeding efficiency does not directly lead to organic evolution; it may hinder survival rather than promote it.

7. **Evaluating the Fourth Option (Intraspecific Competition)**:
- Intraspecific competition refers to competition among individuals of the same species. While this can lead to natural selection, it does not explain organic evolution as effectively as interspecific competition.

8. **Conclusion**:
- Based on the analysis, the correct answer is that organic evolution is due to **interspecific competition**.

### Final Answer:
According to Darwin, organic evolution is due to **interspecific competition**.

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