What action must a driver take upon hearing a siren from an emergency vehicle?

When a driver hears a siren from an emergency vehicle, the appropriate action is to pull over to the right and stop. This ensures that the emergency vehicle can pass through traffic safely and quickly, allowing it to respond to a situation without delay. Stopping helps maintain the flow of traffic and avoids potential accidents that could occur if drivers were to speed up or continue driving at the same speed while the emergency vehicle is maneuvering through. It is a crucial responsibility for drivers to both yield and create a clear path for emergency responders, as their timely arrival can be vital in emergencies.