[MidB] Martha can brush her teeth on her own, but she often…
[MidB] Martha can brush her teeth on her own, but she often forgets to floss afterward. To increase the likelihood that she flosses, her mom places a flosser right next to Martha as soon as she finishes brushing her teeth. Each day, her mom gradually moves the flosser closer to its original spot in the drawer. Over time, Martha begins flossing on her own, even when the flosser is no longer placed near her. Which of the following is Martha’s mom using to evoke flossing?
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