What is meant by the term "thrown switch"?

The term "thrown switch" refers specifically to a switch that has been positioned or moved to facilitate the diversion of train cars from one track to another. When a switch is thrown, it indicates that the mechanism has been manipulated to align the tracks in such a way that trains can change direction, allowing for safe and efficient movement through a rail yard or to different lines. Understanding this function is crucial for ensuring effective train operations and minimizing the risk of derailments or collisions.

By contrast, the other options describe conditions that do not accurately represent what a thrown switch entails. A thrown switch signifies an operational change, whereas damage would imply that the switch is unusable. Incorrect settings also describe a malfunction that would not be referred to as "thrown." Emergency use only does not apply as thrown switches are part of standard operations, not limited to emergencies. Hence, the definition tied to safe and operational track changes underscores why the second choice is the most accurate representation of a thrown switch.