AP Psychology Practice Test 2025 - Free AP Psychology Practice Questions and Study Guide

The control condition is best defined as the group used as a benchmark to measure the effect of the treatment. This group does not receive the experimental treatment or intervention and is often exposed to a placebo or standard treatment instead. The purpose of having a control condition is to provide a point of comparison, allowing researchers to determine whether the changes observed in the experimental group are truly due to the independent variable being tested. This comparative aspect is essential for establishing the validity of the findings in an experiment.

The other options describe different aspects of experimental design but do not capture the essence of what a control condition represents. For instance, the group receiving the experimental treatment refers to the experimental condition rather than the control condition. Ensuring all participants are treated equally pertains to the method of conducting the experiment rather than defining control. The technique used to manipulate the independent variable applies to how researchers change conditions or interventions in the study, not the role of the control group itself.