After experiencing electric shock, what is the best description of Peter's reaction to the fence wires?

The best description of Peter's reaction to the fence wires after experiencing an electric shock is positive punishment. In this context, positive punishment occurs when an unpleasant stimulus (the electric shock) is added following a specific behavior (touching the fence wires), which decreases the likelihood of that behavior occurring in the future.

When Peter touches the fence and receives an electric shock, he is likely to associate the pain he experienced with the action of touching the fence. This association will discourage him from repeating that behavior in the future, demonstrating how positive punishment effectively alters behavior through the introduction of an aversive consequence.

In this scenario, positive punishment emphasizes the addition of the electric shock as the aversive stimulus, which is key to understanding why this option is the most accurate descriptor of Peter's reaction.