Question 7 internal validity refers to the applicability of treatment effect across subgroups within an experiement or across different populations and settings. a. true b. false

The statement above is FALSE.
Internal validity is a term that is used in research, it refers to the causal relationship between the variables in a particular experiment. Internal validity seeks to find out if the variations or effects experienced in the experiment is cause by the expected variable; it seeks to find out the degree of cause and effect relationship in a study.
An experiment can have either a low high internal validity or a high internal validity. A low internal validity implies that there is little or no evidence of causability while a high level of validity implies that there is strong evidence of causability.
An external validity on the other hand, refers to the generalizability of the study and how it compares to other populations.

I’d say either a or d i’m sorry if it’s incorrect.