Which factor affects external validity?

• A. The Sampling Method
• B. The Journal's Prestige
• C. The Researcher's Salary
• D. The Color of the Survey Form

Answer: (A)

External validity is about whether findings apply beyond the specific people, places, and times of the study. The sampling method directly shapes this because it determines how representative the sample is of the broader population you want to generalize to. If you use a biased or narrow sample, the results may not hold for other groups, settings, or moments, undermining generalizability. A sound sampling approach—such as random or stratified sampling—helps ensure the sample reflects the target population, strengthening external validity.

The journal's prestige doesn't change how generalizable the results are; it affects visibility and credibility. The researcher's salary relates to resources, not the extent to which findings apply elsewhere. The color of the survey form is unlikely to determine generalizability, though it might influence response tendencies in some contexts, it doesn't address whether the results extend beyond the study sample.