Final answer:
Traffic signs with a red circle and a red slash indicate a prohibition or restriction.
Step-by-step explanation:
Traffic signs with a red circle and a red slash indicate a prohibition or restriction. These signs usually indicate actions that are not allowed, such as no entry, no parking, no U-turn, or no left turn.
The red circle and slash serve as a universal symbol to convey that a certain action is prohibited or restricted.
For example, a regulatory sign with a red circle and a red slash over a pedestrian symbol means no pedestrians are allowed in that area.
Similarly, a sign with a red circle and a red slash over a bicycle symbol means no bicycles are permitted in that area. These signs are important for ensuring road safety and compliance with traffic regulations.