When approaching an intersection, a driver observes that the traffic signal light is continuously flashing yellow (持续闪烁的黄灯). What must the driver do?

1. Accelerate quickly to clear the intersection before the light turns red
2. Slow down, observe surrounding traffic conditions, and pass safely with caution (确认安全后通过)
3. Come to a complete stop for at least 3 seconds before proceeding
4. Make an immediate right turn only; going straight is prohibited