You are on a road outside of a built-up area, and a car in front of you is driving much slower than is permitted to and has the capacity to. What is the right course of action?

In this situation, both of your chosen answers are correct. When a slower vehicle is ahead of you outside of a built-up area, German traffic rules require that you act considerately. You can adjust your speed to match the slower vehicle if overtaking is not immediately possible. If it is safe and legally allowed, you may overtake at a suitable location. However, it is not permitted to pressure the driver ahead, for example by flashing your headlights, as that can be seen as aggressive behavior and is not allowed. The rules emphasize safe, patient, and respectful driving, with overtaking allowed only when it is safe to do so.