What does a flagger's signaling with a paddle indicate?

Answer: B — Whether to stop or proceed for approaching vehicles

A flagger's signaling with a paddle primarily indicates whether approaching vehicles should stop or proceed. The paddle typically features clear, bold markings such as "STOP" on one side and "SLOW" on the other, providing direct guidance to drivers in construction zones or areas where traffic control is necessary. When a flagger raises the paddle with the "STOP" side facing the oncoming traffic, it signals drivers to come to a complete halt. Conversely, when the flagger displays the "SLOW" side, it instructs vehicles that they may proceed but should do so with caution. This signaling is crucial for maintaining safety in work zones, protecting both workers and drivers. The other options focus on different traffic management scenarios that are not direct functions of flagger paddle signals. For instance, signaling to exit the highway, change lanes, or park safely involves distinct traffic control measures and usually requires different types of signage or guidance.