You are driving a motor vehicle with a manual gearbox. What is the logical thing to do so that the cruise control system can contribute to a fuel-efficient driving style?

To drive fuel-efficiently with a manual gearbox while using cruise control, it's crucial to select the appropriate gear. This allows the engine to operate at optimal RPM, improving fuel efficiency. In addition to this, using cruise control in stop-and-go traffic is not advisable as it can lead to inefficient driving and increased fuel consumption. Finally, anticipating inclines and accelerating in good time helps maintain speed without over-revving the engine, which can waste fuel.

Combining these strategies ensures that the vehicle operates efficiently, adheres to good driving practices, and aligns with traffic regulations aimed at promoting fuel efficiency and safety on the road.