Answer:
A) The young couple's cruelty has shattered Miss Brill's happy delusions about her significance in the world.
C) Miss Brill is confronted with the painful reality of the way she is perceived in society: as old and irrelevant.
Explanation:
The young couple's terrible behaviors have broken Miss Brill's bright ideas about her importance, and she feels a deep loss. The young couple's actions have shown Miss Brill that she is not as significant to others as she thought. Miss Brill learns that people see her as elderly and unimportant. The young couple she was with was rude and didn't care about her. She felt underappreciated.
C. We’re enchanted with his new windmill, nothing so pretty and so wonderful had ever been seen.
It might be D i might be wrong on that