Final answer:
EMTs are most commonly struck by vehicles at a collision scene because drivers are distracted by the emergency and not paying attention to the road.
Step-by-step explanation:
The common reason that Emergency Medical Technicians (EMTs) are struck by motor vehicles at the scene of motor vehicle collisions on roadways is because drivers are distracted by the scene of the collision and do not pay attention to what they are doing. This is a perilous situation as EMTs are focused on providing critical care to patients, often under stressful and chaotic conditions. The presence of emergency vehicles, flashing lights, and rescue operations can take drivers' attention away from the road, leading to unfortunate incidents where EMTs are hit by moving vehicles.