What would the independent, dependent, and control be for the study of inattentional blindness and alcohol be?

In a study involving inattentional blindness, they chose subjects who were given alcohol and those who were not. They were told to watch a video of people in white shirts ping a ball and asked after the video whether they had seen the gorilla. I think the independent variable would be those who received alcohol. I think the dependent variable would be inattentional blindness but maybe there is more to elaborate on this. I think the control group are those who received the placebo. Any guidance on this is appreciated. Thank you