In an experiment to test the effects of sleep on cognitive performance, participants are randomly assigned to either 8 hours of sleep or 4 hours of sleep for one night. The next day, all participants complete a series of cognitive tasks, and their performance scores are recorded. What is the dependent variable in this experiment?

• A. The amount of sleep each participant gets
• B. The type of cognitive tasks
• C. The performance scores on the cognitive tasks
• D. The time of day the tasks are completed

Answer: (C)