Theory of natural selection dwells on

Options

A. role of environment in evolution
B. natural selection acting on favourable variations
C. changes in gene complex resulting in heritable variations
D. None of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding the Theory of Natural Selection**: The theory of natural selection was proposed by Charles Darwin. It is a fundamental concept in the study of evolution, explaining how species evolve over time.

2. **Key Mechanism of Evolution**: Natural selection is considered a key mechanism of evolution. It describes the process through which certain traits become more or less common in a population based on their impact on the survival and reproduction of organisms.

3. **Role of the Environment**: The environment plays a crucial role in natural selection by determining which traits are favorable. Organisms with traits that are better suited to their environment are more likely to survive and reproduce.

4. **Favorable Traits**: The traits that enhance an organism's ability to survive in its environment are referred to as favorable traits. These traits are selected by the environment and can be passed on to future generations.

5. **Evaluating the Options**: When presented with options regarding what the theory of natural selection dwells on, we need to identify which option accurately reflects the essence of this theory.

- **Option 1**: "Role of the environment in evolution" - While this is related, it does not fully capture the mechanism of natural selection.
- **Option 2**: "Natural selection acting on favorable variations" - This option correctly emphasizes the process of natural selection acting on variations that are favorable for survival and reproduction.
- **Other Options**: They may discuss genetic changes and heritable variations but do not focus specifically on the selection process.

6. **Conclusion**: Based on the evaluation, the most suitable answer is **Option 2**, which highlights that natural selection acts on favorable variations, leading to the evolution of species.

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