Answer:
Option A.
Explanation:
The school setting from Galarza's Barrio Boy shapes the narrator's understanding of what it means to be american. Because Ernesto sees that children from many cultures are in the class, he learns that Americans are diverse. This relates to the main theme of the story, which is the immigrant's experience with all of its feelings, through the eyes of a young boy.
When Ernesto starts school in America he is opened to a new experience of multiculturalism in which he needs to finds his own place and voice, and where he learns that "to be American" means diverse things to different people.
