Final answer:
The subject of this question is Driving and it discusses the potential hazards that a motorist may encounter while driving.
Step-by-step explanation:
Based on the given information, the subject of this question is Driving.
The question is discussing the potential hazards that a motorist may encounter while driving, specifically referring to vehicles, pedestrians, or other objects in motion within a 12-15 second search.
This highlights the importance of maintaining awareness of one's surroundings while driving and being prepared to react to any potential hazards.