The 55-mph speed limit was introduced in the U.S. in 1973. Shortly thereafter the number of auto accidents declined. We can conclude that:
A) the reduced speed limit caused the decline in auto accidents.
B) the reduced speed limit may have caused the decline in the number of auto accidents.
C) the reduced speed limit and the number of auto accidents are causally related.
D) the reduced speed limit had nothing to do with the decline in auto accidents.

Question

The 55-mph speed limit was introduced in the U.S. in 1973. Shortly thereafter the number of auto accidents declined. We can conclude that:​
A) ​the reduced speed limit caused the decline in auto accidents.
B) the reduced speed limit may have caused the decline in the number of auto accidents.​
C) the reduced speed limit and the number of auto accidents are causally related.​
D) the reduced speed limit had nothing to do with the decline in auto accidents.​

Quizplus · Accepted Answer

While the introduction of the 55-mph speed limit may have contributed to the decline in auto accidents, there may have been other factors at play as well. Therefore, we can only conclude that it may have caused the decline in the number of auto accidents. Option A and C are too strong and absolute statements, and option D is too extreme and dismisses any possible connection between the two.

The 55-Mph Speed Limit Was Introduced in the U