In regard to internal and external validity
A) you can't have one without the other.
B) procedures used to establish internal validity will also establish external validity.
C) they are matters of degree rather than all-or-nothing propositions.
D) neither is important in laboratory experiments.
E) internal validity is a much more important issue in marketing than external validity.

Question

Quizplus · Accepted Answer

Internal and external validity are not all-or-nothing; they can vary in degree, meaning a study can have high or low levels of each.

In Regard to Internal and External Validity