You are in your car towing a trailer which has no brakes and you approach a long steep downhill slope. What is correct?

The correct combination of answers emphasizes the importance of safety and control when towing a trailer without brakes, especially on steep downhill slopes.

1. Reducing speed is crucial to prevent the trailer from pushing the car uncontrollably. Engaging low gear helps maintain a safe speed and provides better control while braking. This aligns with the German traffic rule that requires drivers to adjust their speed according to road conditions.

2. Making allowance for the pushing effect of the trailer acknowledges the dynamics involved when the trailer can exert force on the towing vehicle. Understanding this effect is essential for maintaining control and preventing accidents, as the trailer can easily push the car if too much speed is maintained or braking is insufficient.

The option of relieving car brakes by disengaging the clutch at frequent intervals, while it may seem beneficial in theory, can potentially lead to loss of control, especially if not executed properly. It is not relevant for this scenario and isn't part of the correct answer.

In summary, recognizing the interactions between the towing vehicle and the trailer, combined with speed management, is vital for driving safety, particularly in challenging conditions like steep descents.