Answer:
D-neither. The sentence is good the way it is, and you don’t capitalize the or adults, so the only option in neither.
In fiction, a foil is a character who contrasts with another character, usually the protagonist, to highlight qualities of the other character.
Yes. It's a metaphor because the writer is not implying that the boy is actually a pig; his actions represent a pig. And thus, it is a metaphorical phrase, nonetheless an actual description!
The answer is should be b