Help please! <3 thank you!!

I would have to say D.

Explanation: D is the best answer to me because all of the other ones don't have to do with a population change in different areas, and it makes sense for pollution to increase and natural resources to decrease if everyone is starting to move to the city (urban areas).

I hope I helped mate.

it continues in business

answer; eliminate parking problems in cities, because a car took up only half as much space as a horse and buggy;