Answer: a chart that displays road fatalities in states that have different driving ages
Step-by-step explanation:
If one wanted to show that increasing the driving age would lead to less fatalities on the road, they would need to show evidence that points to this theory.
One way to do so is to compare different states. States generally set their own driving age which is why some states have a higher driving age than others. Fatalities in states that have a higher driving age can be juxtaposed against states that have a lower driving age to see if there is a difference.
This information can be depicted in a chart for easier comparison where it will readily show the effect of increasing the driving age vs leaving it at relatively lower ages.