On the door of the refrigerator is a sheet of paper with check marks on it. Every time Alice cleans her room properly and makes her bed, she receives a check mark. When she accumulates 100 check marks, she can get the new video game she wants. What type of behavioral program are Alice's parents using?
◦ negative reinforcement
◦ positive punishment
◦ token economy
◦ systematic desensitization
◦ modeling