What is external validity primarily concerned with?

• A. The degree to which findings generalize to other subjects and situations
• B. The accuracy of the study's findings independent of extraneous variables
• C. How realistic the experimental setting is relative to real life
• D. The extent to which a measure appears valid

Answer: (A)

External validity is about generalizing findings beyond the study sample to other people and contexts. It asks whether the results would hold for different populations, settings, and times, not just in the exact conditions of the original study. For example, if a treatment works for college students in a controlled lab, external validity questions whether it would apply to older adults in community clinics or in real-world practice. That broad generalization focus is why this option is the best. The other ideas describe different concepts: internal validity concerns ruling out confounds so the effect is truly due to the manipulation, ecological validity is a specific facet about how realistic the setting is relative to real life, and face validity is about whether a measure appears valid at a glance, not about generalizability.