In a Within-Subjects Study That Extends Over a Relatively Long

Multiple Choice

In a within-subjects study that extends over a relatively long time,it is possible that there will be systematic changes in the participants' skills or knowledge during the time of the study.If these changes influence the participants' scores,causing scores at the end of the study to be different from scores at the beginning,the effect is called

A) a history effect.
B) instrumentation.
C) maturation.
D) regression toward the mean.