What should be observed when driving a quad?

The selected combination is entirely correct and reflects important safety regulations when driving a quad.

1. Wearing protective motorcycle clothing is essential for safety. It significantly reduces the risk of injury in the event of an accident, as quads can often be less stable than cars.

2. Carrying a warning triangle is crucial as well; it ensures that in case of a breakdown, you can alert other drivers and enhance your visibility, which is a requirement outlined in German traffic law.

3. The necessary steering force being greater than with a car highlights the different handling characteristics of quads. Drivers need to be aware that maneuvering a quad is different and may require more physical effort, which can affect control in various situations.

Overall, all three points are vital for ensuring safety and compliance with German traffic regulations when operating a quad.