Affect - someone causing something.
Effect - the result of what was caused.
EX: Destroying trees negatively affects the wildlife.
EX: The effect that destroying trees has on wildlife is negative.
In chapter 8 of the Red Badge of Courage, the thing that caused Henry to turn back to the frontline after fleeing is that He heard loud noises and was curious.
They both shared a vision of an "agrarian" American utopia, that is, relating to farms and farming. They believed their perfect land lies in the fields and with the workers and farmers.
The answer is A, to contrast elements within the text.
hope this helps!
