A researcher conducts a study on a population and gets some results. To generalize these results to a different population, which of the following should be shown in the measurement?

External validity shows that results can be generalised to a different population or setting.

Internal validity concerns whether the study established genuine causation.

Emissary validity is not a recognised type of validity.

Divergent validity shows that a measure differs from unrelated constructs.

Representative sampling strengthens external validity.

External validity often trades off against tight laboratory control.