Who expanded upon Pavlov's research findings?

The choice of Skinner as the correct answer is based on the fact that he significantly built upon and expanded Pavlov's findings through his own research on operant conditioning. While Pavlov focused on classical conditioning—associating an involuntary response with a stimulus—Skinner introduced the concept of reinforcing behavior through rewards and punishments, which is central to operant conditioning.

Skinner conducted experiments with animals, most famously with rats and pigeons, demonstrating how behaviors could be shaped and modified through reinforcement. This approach highlighted the role of consequences in learning and behavior, which provided a more comprehensive understanding of how behavior can be influenced beyond just the conditioned responses studied by Pavlov.

Understanding Skinner's contributions helps to recognize the evolution of behavioral theories in psychology and education; his work lays the foundation for behaviorist approaches that have been widely applied in various educational settings.