A Researcher Records the Number of Motorcycle Fatalities Before and After

Multiple Choice

A researcher records the number of motorcycle fatalities before and after the implementation of a mandatory helmet law.During the same period,she compares this number to the number of motorcycle fatalities of three states that do not have a mandatory helmet law.This research design would be an example of a(n) _____ design.

A) true experiment
B) single case
C) interrupted time series
D) control series