What is the correct course of action in this situation?

In the given scenario, you're faced with a situation that likely involves wet road conditions indicated by the rain and the caution sign suggesting slippery roads. The correct actions—reducing speed and avoiding abrupt steering movements—are essential for maintaining control of the vehicle in these conditions.

Reducing speed helps to ensure that you have more time to react to any unexpected hazards and decreases the likelihood of skidding. Avoiding abrupt steering movements is crucial because sharp turns can destabilize the vehicle and lead to loss of traction, especially on slippery surfaces. Braking hard should be avoided, as it can exacerbate skidding and loss of control.

These actions align with the principles found in German traffic regulations which emphasize the importance of adapting driving behavior to road conditions to ensure safety for all road users.