What reason was given for Mrs. Starch's knowledge of student rumors?

Mrs. Starch's knowledge of student rumors was attributed to her hearing aid, which suggests that she was able to overhear conversations and gossip among the students. This capability allowed her to stay informed about what was being said, even if it was not directed at her. Her hearing aid plays a crucial role in enhancing her awareness of the environment, enabling her to catch snippets of conversations that others may not notice. This would provide her with insights into the students' thoughts and opinions, thereby keeping her in the loop regarding their rumors. The other options, while they might suggest potential reasons for a teacher's insight into student behavior, do not specifically address the unique advantage that a hearing aid would provide in this context.