Final answer:
Lilly's nagging was effective as a form of negative reinforcement, increasing the likelihood that Jason will take out the trash promptly in the future to avoid the nagging.
Step-by-step explanation:
Lilly's nagging behavior can be understood in terms of operant conditioning, which is part of behavioral psychology. When Jason takes out the trash to stop Lilly's nagging, he is negatively reinforced - the unpleasant stimulus (nagging) is removed when he performs the desired behavior (taking out the trash), increasing the likelihood he will do it again in the future to avoid the nagging. Therefore, Lilly's nagging has thus been effective in reinforcing the behavior of taking out the trash promptly.