It is the use of C. a flashback.
A flashback refers to a scene that happened before in the timeline. So if you are writing something in a chronological manner, it means that you are going to write it in the order that the events happened. If you suddenly introduce a flashback, you are going to break the flow of chronological events.
C. They are too perfect to exist.
Computers should be used in all fourth grade classrooms to enchance students technical ability
