What denotes signal to stop when waved violently on or near the track?

The correct response indicates that a warning from a crew member, particularly when signaled violently, conveys an urgent message to stop. This action is crucial for ensuring the safety of both the crew and any equipment on or near the tracks. When a crew member waves their arms or a flag in a vigorous manner, it is an immediate indication of an existing danger, requiring all personnel and trains in the vicinity to halt operations.

This type of visual signal is a practical tool for communication in scenarios where verbal commands may not suffice due to distance or noise. It reflects the crew's awareness of the situation and their responsibility in preventing accidents. A clear understanding of this signaling method is essential for all personnel to maintain safety and ensure proper protocol is followed on the tracks.