Answer:
Secondary reinforcement
Explanation:
Secondary reinforcement has to do with a scenario where a response reinforces a behavior after being previously associated with reinforcers which are naturally occurring in the sense that they require no effort or form of learning. The natural reinforcers are called primary reinforcers and they include air, food, sleep and air. Gillian's kids were to be given a reward after they were done with an approved chore which is a form of secondary reinforcement. However the difference between Gillian rewarding and bribing her kids is that she rewarded after they were done with the chore and not before.