What type of turn signal is required on a bus or trailer wider than 80 inches?

Buses or trailers that are wider than 80 inches are required to have electric turn signals that transition from amber to red. This specification is important because it helps ensure that the signaling system is highly visible and easily understood by other drivers on the road.

Using an amber light for the turn signals alerts surrounding motorists to the intention of the vehicle to turn or change lanes, which is critical for safety on the road. The color amber is associated with caution, indicating to nearby drivers to pay attention to the maneuver. When the signal changes to red, it conveys a further level of warning and clarity about the stop or turn being made. This requirement ensures compliance with safety regulations while providing a clear signal to other drivers, thus enhancing roadway safety.

The other options do not fit the specific requirements outlined for larger vehicles like buses or trailers, either by not adhering to color standards or being less effective in communication on the road.