It is important to know the author's purpose because knowing the author's purpose can change how the story is being told. If someone said,"Mom, I would really like this new video game for my birthday." and the author's purpose was to inform, it would be informing the mom that the person wanted the video game. If the author's purpose was to persuade, that person would be persuading the mom to get him the video game.
B.
The word “incredulity” is defined as
“the state of being unwilling or unable to believe something.” Which is not the case in the sentence
Example of the word incredulity: "he stared down the street in incredulity"
Answer: I haven't read the book so please take this with a grain of salt but I believe the answer would be C, "As teenagers get older, parents should help them avoid more serious negative consequences." Exerting control might be too much, letting the teenager be too rebellious would lead to disobeyment, and letting them do it again isn't a good idea. I apologize if you get the answer wrong, good luck!
I think its C because they talk about hurting the slaves.