You are driving a motor vehicle with a manual gearbox. What type of behaviour pollutes the environment?

The selected combination, consisting of an uneven driving style and frequently pressing the accelerator while waiting at traffic lights, is correct because both behaviors contribute significantly to environmental pollution.

1. An uneven driving style leads to unnecessary fuel consumption and increased emissions. It indicates rapid acceleration and deceleration, which not only affects fuel efficiency but also raises pollutant output.

2. Frequently pressing the accelerator while waiting at traffic lights unnecessarily consumes fuel and produces exhaust emissions while the vehicle is stationary. This practice worsens air quality and is considered wasteful.

On the other hand, driving downhill in a high gear is not an environmentally damaging behavior by itself. In fact, it can actually conserve fuel under certain conditions, as it allows the vehicle to maintain speed without excessive acceleration.

Understanding these behaviors is important as they directly relate to regulations aimed at reducing vehicular emissions and promoting eco-friendly driving practices in Germany. The aim is to minimize the environmental impact caused by motor vehicles.