Campbell's "Reforms as Experiments" Article Includes a Description of an Evaluation

Multiple Choice

Campbell's "reforms as experiments" article includes a description of an evaluation of a state police crackdown on speeding in Connecticut. There were 324 fatalities in the year before the crackdown and 284 in the year after. According to Campbell, the program was partially the cause of the drop, but ______ also occurred.

A) selection
B) maturation
C) instrumentation
D) regression to the mean