The correct answer is letter A. The purpose of the author in writing the story is to persuade. The book is divided into 5 parts and it dwells in many different issues like poverty, lying, alcoholism, among others. It focuses on the characters having tenacity and the challenge of facing difficult situations through a self-determined goal and outlook in life.
A "flat character" is essentially a character who doesn't change throughout a story. They are seen as "stagnant" and remain the same, so it doesn't affect the storyline.
