Tara decides that Emily's inattention to detail and general detachment from school stem from the fact that Emily is too preoccupied by her job. Which theory is Tara using to come to this explanation

Martha participates in a research study in order to receive extra credit for her psychology class. when she arrives in the research office she is given a can of what looks and tastes like beer, but which actually contains no alcohol. in the adjoining room martha's classmate karen is also participating in the study. karen receives a can of alcoholic beer. if the experiment was designed to test the effects of alcohol on concentration, then who is exposed to the independent variable?