What is the correct course of action in this situation?

Your choice to perform an emergency braking manoeuvre is correct because when approaching a hazard such as a sudden obstruction, stopped vehicles, or a red traffic light, German traffic rules require you to reduce speed quickly and safely to prevent accidents. Emergency braking is used when an immediate and strong deceleration is needed to avoid a collision.

Continuing to drive ready to brake (option 2) is not sufficient if a sudden stop is necessary, as delaying braking could cause an accident. Accelerating (option 3) in this situation is unsafe and against traffic regulations because it increases the risk of collision with stopped vehicles ahead.

In summary, the rule is to always react promptly and with appropriate braking intensity to hazards to maintain safety. Emergency braking is the correct action when a sudden stop is required to avoid danger.