Final answer:
A trainer should choose a receptive dog that is still learning the skill to effectively demonstrate the training process and portray realistic training development.
Step-by-step explanation:
When selecting a demo dog in class, a trainer should choose a dog that is receptive to the trainer but is learning the skill for the first time. This approach allows for a realistic demonstration of the training process, showcasing both the challenges and successes that come with dog training. A well-socialized, obedient dog that is focused and learns quickly is ideal as it shows great promise as a service dog, as evidenced by the outcomes seen at The Seeing Eye campus where such traits are sought after in dogs graduating to become service animals. Dogs with these characteristics can illustrate the effect of proper training methods, as opposed to dogs that are excessively fearful or disruptive, which might not provide the most effective learning experience for students.