As with any author's decision to use 1st person, her intention most likely -- in this story -- was to get her readers to go along for the ride into madness and cultivate a certain amount of sympathy for the narrator and her plight. The constant use of "I" puts readers in the narrator’s head and allows them to empathize with her.
The answer is B! With books about only white children, black children don’t feel connected to them.
