Darwin judged the fitness of an individual by

Options

A. Ability to defend itself
B. Strategy to obtain food
C. Number of offsprings
D. Dominance over other individuals

Explanation

**Step-by-Step Solution:**

1. **Understanding Darwin's Concept of Fitness**:
- Darwin's theory of evolution emphasizes the concept of "fitness," which refers to an organism's ability to survive and reproduce in its environment.

2. **Factors Influencing Fitness**:
- Fitness is influenced by several factors, including the ability to defend oneself, strategies to obtain food, and dominance over other individuals. However, these factors contribute to the overall survival of the organism.

3. **Reproductive Success as a Measure of Fitness**:
- Darwin placed significant emphasis on reproductive success as the primary measure of fitness. An organism's ability to produce offspring is crucial for the continuation of its genes in future generations.

4. **Natural Selection**:
- According to Darwin, natural selection favors those individuals that are better adapted to their environment. These individuals are more likely to survive and reproduce, thereby passing on their advantageous traits to their offspring.

5. **Conclusion**:
- Therefore, while various factors contribute to an organism's survival, the number of offspring produced is the most critical measure of fitness according to Darwin. The correct answer to the question is that Darwin judged the fitness of an individual by the "number of offspring."

**Final Answer**: Darwin judged the fitness of an individual by the number of offspring.

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