Read the passage from “I Know Why the Caged Bird Sings.” Mrs. Bertha Flowers was the aristocrat of Black Stamps. She had the grace of control to appear warm in the coldest weather, and on the Arkansas summer days it seemed she had a private breeze which swirled around, cooling her. She was thin without the taut look of wiry people, and her printed voile dresses and flowered hats were as right for her as denim overalls for a farmer. She was our side's answer to the richest white woman in town.

The author’s purpose in including this passage is to

explain to the reader the way people dressed in Black Stamps.
instruct the reader on the local customs in Black Stamps.
inform the reader of Mrs. Flowers’s social position in Black Stamps.
teach the reader how Mrs. Flowers’s fashion affected Black Stamps.