Answer:
The independent variable was the:
A- alcohol intake.
Step-by-step explanation:
The dependent variable in a study is the one being measured by that study. The independent variable is the factor researchers control or change in order to affect the dependent variable. In the study described in the question, the researcher wished to measure the reaction time of participants. The independent variable, the factor that was changed to influence the reaction time, was the alcohol intake. Some participants drank one ounce, while others had three ounces of alcohol.