Final answer:
The dog trainer is using shaping to train the dog to use the toilet.
Step-by-step explanation:
The dog trainer is using shaping to teach the dog to use the toilet. Shaping is a technique in which behaviors are gradually reinforced to achieve a desired behavior. In this case, the trainer is reinforcing the dog's behavior of looking at the toilet, getting close to the toilet, sitting on the toilet, and finally urinating in the toilet bowl.
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