Answer:
C) Hyperbole
Step-by-step explanation:
A hyperbole is an exaggerated statement or opinion to convey strong feelings towards something. Saying that the *only* thing students care about is what the other students have to say about them is clearly exaggerated as it is impossible for that to be the only thing they can possibly care about.
This is a very light usage of hyperbole as we see phrases like these being used every day!