Provinces and states with stringent car safety requirements, including required use of seat belts and annual safety inspections, have on average higher rates of accidents per kilometer driven than do provinces and states with less stringent requirements. Nevertheless, most highway safety experts agree that more stringent requirements do reduce accident rates. Which one of the following, if true, most helps to reconcile the safety experts' belief with the apparently contrary evidence described above? ['The roads in provinces and states with stringent car safety requirements are far more congested and ttherefore dangerous than in other provinces and states.', 'Provinces and states with stringent car safety requirements have, on average, many more kilometers of roads than do other provinces and states.', 'Annual safety inspections ensure that car tires are replaced before they grow old.', 'Drivers often become overconfident after their cars have passed a thorough safety inspection.']