In the Example of the Peppered Moths, the Moths Evolved

In the example of the peppered moths, the moths evolved in a darker coloration because:

A) the pollutants covered the moths and made them appear darker.
B) the moths were able to turn black and pass the color to their offspring.
C) a mutation for a darker color took place.
D) the moths that were already darker were selected for.
E) they became nocturnal.