Of the following types of laws, which is most likely to have contributed to a decline in the percentage of drivers involved in motor vehicle fatalities?
◦ Laws in at least 15 states that have raised the drinking age to 23
◦ Laws that prohibit anyone under the age of 18 from driving with any detectable BAC
◦ Laws restricting people with two or more DUIs to use of self-driving cars
◦ Zero tolerance laws for driving while intoxicated