This is a bit subjective, but it could be argued that social change had the biggest change in Southern life, since the abolition os slavery (which was inherently a social issue) led to the biggest changes.
C) New settlers arrived at a steady rate and the population increased gradually
Answer: D. it lies in a valley, surrounded by mountains, that traps in air pollutants over the city.
Explanation: Being in a valley results in air pollution being contained to an area.
Explanation:
answer A hope this helps :)