What best describes the influence of the setting in "My Father Writes to my Mother"?

Father of uncle = grandpa.

daughter of grandpa = aunt/mom

son of mom/aunt is either cousin or brother.

Cousin isn't one of the options so it must be brother.

The statement which best describes the influence of the setting in "My Father Writes to my Mother" is the second choice - B) Mother feels empowered when she is in the company of her sisters and cousins.

The setting are her sisters and cousins, because that is what surrounds the mother. Under their influence, the mother's behavior changes drastically.