Answer:
The phenotype of the moth changed due to natural selection. During the Industrial Revolution, objects in England became a lot darker in color due to the settling of coal pollutants in the air. These light colored moths did not have good camouflage in this environment. Therefore, most of the light colored moths did not survive to reproduce. However, the dark colored moths had better camouflage, and were therefore more likely to survive and reproduce. This lead to a shift towards darker color moths, as they had a higher survival rate than the light colored moths.