What action does sign B6 require from drivers?

Sign B6 is designated as a regulatory sign indicating that drivers must drive straight on. This sign is typically utilized in situations where certain routes are not allowed or where specific directions must be followed, ensuring a smooth flow of traffic. By instructing drivers to proceed straight, it helps maintain order and safety on the road, preventing confusion or unnecessary detours.

The other options represent actions that either do not align with the directive of the sign or are less relevant in the context of what B6 communicates. For instance, turning left would contradict the instruction, yielding to pedestrians pertains to pedestrian rights rather than driving direction, and slowing down while proceeding with caution, although a general safe practice, does not specifically reflect the requirement of driving straight on as dictated by sign B6.