Question

peppered moths in england evolved into a dark - colored form when soot darkened the bark of the trees they lived on and exposed the light - colored form to predation. however, air pollution control eventually restored the moths habitat to its original condition. what would probably have happened to the peppered moth population if the light - colored alleles had been entirely lost from its gene pool during the period when dark - colored moths were selectively favored?

mutations that would reestablish the light - colored allele in the gene pool would have occurred.
the moths would have evolved behaviorally and chosen to avoid trees with light - colored bark.
the population would have become extremely small or possibly extinct after the loss of this adaptive trait.
the moths would have changed their dietary preferences to foods that contain only light pigments.

Explanation:

If light - colored alleles were lost, moths would lack the trait for camouflage on light - colored bark after habitat restoration, leading to decline.

Answer:

The population would have become extremely small or possibly extinct after the loss of this adaptive trait.