A 'Pedestrian Crossing' sign warns drivers to be cautious of what?

Answer: B — Pedestrians crossing the road

The 'Pedestrian Crossing' sign specifically alerts drivers to the presence of pedestrians who may be in the process of crossing the street. It serves as a reminder for motorists to slow down, watch for individuals who might suddenly enter the roadway, and provide them with right-of-way as needed. This sign is vital for ensuring the safety of pedestrians, as they may not always be easily visible or may cross the road unexpectedly. In contrast, while children playing nearby can be a concern for drivers, it is not the primary focus of the 'Pedestrian Crossing' sign. Similarly, road maintenance work and parked vehicles pose different types of hazards and are indicated by different signage, not by a 'Pedestrian Crossing' sign. Thus, the correct answer emphasizes the essential role of the sign in protecting pedestrians in traffic situations.