In " homesick," why does jean finally tell lin nai-nai to say "good day" rather than "sewing machine"?

The answer is letter B. .The narrator's bed flips over, which leads to great confusion and panic among everyone in the house.

choices to this question are:
A.The narrator's cousin thinks that he is suffocating, which leads him to run up to the attic and knock over the narrator's bed.
B.The narrator's bed flips over, which leads to great confusion and panic among everyone in the house.
C. The narrator's aunts are robbed in the middle of the night, which puts everyone on edge.
D. The bed in the attic collapses, which places the narrator's father in grave danger.