The main point of Darwin's theory is `:`

Options

A. variation
B. mutation
C. enormous fertility
D. natural selection

Answer

**Step-by-Step Solution:**

1. **Understanding Darwin's Contribution**: Charles Darwin is known as the father of evolution due to his extensive work on the theory of evolution. His research laid the foundation for understanding how species evolve over time.

2. **Key Concept - Natural Selection**: The main point of Darwin's theory is the concept of natural selection. This principle states that organisms that are better adapted to their environment are more likely to survive and reproduce.

3. **Role of Variations and Fertility**: Darwin's theory also emphasizes the importance of variations within species. These variations can lead to differences in survival and reproduction rates. Enormous fertility, or the ability to produce many offspring, is crucial because it increases the chances of some individuals having advantageous traits.

4. **Survival of the Fittest**: A key phrase associated with Darwin's theory is "survival of the fittest." This means that those individuals who are most suited to their environment will survive and pass on their traits to the next generation.

5. **Conclusion**: Among the options provided (variations, mutations, enormous fertility, natural selection), the main point of Darwin's theory is **natural selection**. This concept encapsulates the process by which evolution occurs.

**Final Answer**: The main point of Darwin's theory is **natural selection**.

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