The eastern grey squirrel lives mostly in oak trees that have a medium gray bark. in some cities, oak tree bark is darkening due to air pollution. this eastern grey squirrel shows melanism, or the increase in black pigment in its fur. what is most likely the reason for the change in fur color? a) with age; this is a very old squirrel. b) squirrels from another region moved into the area. c) it is a way to the grey squirrel attract a mate. d) it is a way to camouflage the squirrel in a changing habitat.