How were participants matched in Raine's study?

• A. By their intelligence levels
• B. By age and sex
• C. By their socioeconomic status
• D. By their previous criminal history

Answer: (B)

In Raine's study, participants were matched by age and sex to reduce the influence of these variables on the outcomes of the research. Matching by age ensures that any differences observed in brain activity or behavior can be more accurately attributed to other factors being studied, rather than age-related differences. Additionally, matching by sex controls for potential biological and social influences that could skew the results. This method enhances the validity of the findings by ensuring that the groups being compared are similar in these important demographic aspects, allowing researchers to draw more reliable conclusions about the specific variables of interest in the study.