Phenomenon of industrial melanism demonstrates

Options

A. geographical isolation
B. reproductive isolation
C. natural selection
D. induced mutation.

Explanation

**Step-by-Step Solution:**

1. **Understanding Industrial Melanism**:
- Industrial melanism refers to the phenomenon where darker-colored individuals of a species become more common in industrial areas due to pollution. This is particularly observed in the Biston moths in England.

2. **Pre-Industrial Revolution Scenario**:
- Before the Industrial Revolution, the environment was characterized by light-colored lichens covering tree barks. The Biston moths had two varieties: the light-colored (Biston betularia) and the dark-colored (Biston carbonaria).
- The light-colored moths had a survival advantage because they blended in with the light-colored lichens, making it difficult for predators to spot them.

3. **Impact of the Industrial Revolution**:
- The Industrial Revolution led to increased pollution, resulting in the death of lichens and the deposition of black soot on tree barks.
- This change in the environment favored the dark-colored moths, as they could now blend in with the soot-covered surfaces.

4. **Natural Selection**:
- The shift in the environment demonstrates natural selection, where the advantageous trait (dark coloration) increases the survival and reproductive success of the dark moths.
- As a result, the population of dark moths increased, while the population of light moths decreased because they were more easily spotted by predators.

5. **Conclusion**:
- The phenomenon of industrial melanism illustrates the process of natural selection, where environmental changes can shift the advantages of certain traits within a population.

**Final Answer**: The phenomenon of industrial melanism demonstrates natural selection.

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