At the National Zoological Park in Washington,D

Multiple Choice

At the National Zoological Park in Washington,D.C.,a polar bear suffered a broken tooth,and keepers needed a safe way to treat the problem.The bear was rewarded first for sticking its nose through a slot in the cage door,then for allowing a keeper to lift its lip and touch its teeth.Finally,a veterinarian was able to treat the damaged tooth while the bear waited placidly for its familiar reward.This is an example of _______.

A) modelling
B) shaping
C) negative reinforcement
D) secondary learning