Answer:
The statement "The precision of the instruments used in measuring DV" has nothing to do with external validity.
Step-by-step explanation:
External validity pertains to the generalization of the research findings to populations, settings, and times beyond the specific conditions of the study. It involves assessing whether the results of a study can be applied to the real world or other contexts. The other factors mentioned—ethnicity of participants, season of the study, and the setting of the study.