A research psychologist has participants serve as their own control group by having them take part in every condition of his study. This experimental approach is an example of a (n) Group of answer choices one-shot case study. independent groups design. simple random design repeated measures design.

repeated measures design.

Explanation:

Repeated measures design: In psychology, the repeated measures design reduces or diminishes the variability effect because the researcher uses the same subject throughout the research process. By using the repeated measures design the experimenter makes appropriate statistical conclusions by examining a small subjects set.

Example: Longitudinal study.

In the question above, the experimental approach is an example of repeated measures design.