The Nonequivalent Comparison Group Design Can Yield Several Possible Outcomes

Multiple Choice

The nonequivalent comparison group design can yield several possible outcomes. In one scenario, the experimental group scores higher than the control group at the start of the experiment, and only the experimental group's scores increase from pretesting to posttesting. This could reflect an influence of the independent variable. However, it could also reflect

A) a local instrumentation effect.
B) a attrition effect both groups.
C) simply that the experimental group was studied for a longer time period than the control group.
D) selection-maturation effect.