If all exterior headlights suddenly extinguish simultaneously while driving on an unlit rural road at night, what is the proper emergency protocol?

1. Continue driving at the same speed relying on memory of the road
2. Turn on hazard warning flashers and clearance lamps immediately, maintain lane tracking, apply brakes gently to slow down, and pull safely off the roadway onto the shoulder (开启示廓灯和危险报警闪光灯，减速靠边停车)
3. Honk the horn continuously and accelerate
4. Turn on interior cabin dome lights to illuminate the road outside