What was the term given by Darwin for the differences in characteristics?

Options

A. Natural selection
B. Fitness
C. Evolution
D. Variation.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term used by Charles Darwin to describe differences in characteristics among organisms.

2. **Analyzing the Options**:
- **Natural Selection**: This is a process by which organisms that are better adapted to their environment tend to survive and produce more offspring. While it is a key concept in Darwin's theory, it does not specifically refer to differences in characteristics.
- **Fitness**: In the context of evolution, fitness refers to an organism's ability to survive and reproduce in its environment. It is related to natural selection but does not directly describe the differences in characteristics.
- **Evolution**: This term refers to the change in the heritable characteristics of biological populations over successive generations. It is a broader concept that encompasses various processes, including natural selection.
- **Variation**: This term specifically refers to the differences in characteristics among individuals within a population. It is the correct term that Darwin used to describe these differences.

3. **Identifying the Correct Answer**: After analyzing all the options, the term that Darwin used for the differences in characteristics is **variation**.

4. **Conclusion**: The answer to the question is that the term given by Darwin for the differences in characteristics is **variation**.

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