Teacher:Given a travel related situation, and given a specific question about the situation, summarize the question into a title
Teacher: Now, understand the problem? Solve this instance: On a flight with Air Transat, passengers were informed that for use in the in-flight entertainment system, only earbud style earphones were permitted.

I ignored this and used my on-ear style earphones (I hate earbud style earphones), and the cabin crew did not tell me to take them off. I could still clearly hear announcements, and in any case, those announcements could be transmitted through the audio of the in-flight entertainment system, so being unable to hear important ambient sounds does not seem a reasonable motivation.

Why would only earbud style earphones be permitted? Is this rule common and commonly enforced?

Student:
Why only earbud style earphones?