The most likely correct explanation for the dark-color trait in the Peppered Moth is: The dark-colored trait for the Peppered Moth was a color variation that was present before the Industrial Revolution occurred.
This response aligns with the observed phenomenon during the Industrial Revolution, where pollution led to darker surfaces on which the moths rested, favoring the survival of the dark-colored moths due to better camouflage from predators. The dark trait was not newly acquired in response to environmental changes; rather, it was pre-existing in the population and became advantageous due to those changes.