John B. Watson contributed to educational practice by demonstrating:

John B. Watson is widely recognized for his role in establishing the foundation of behaviorism, which emphasizes the study of observable behaviors rather than internal states like emotions or thoughts. His contributions to educational practice are most prominently linked with the application of behaviorist principles, particularly through classical conditioning.

Watson's famous experiment with "Little Albert" illustrated that emotional responses could be conditioned in humans, just as Pavlov showed with dogs. This work provided insights into how behaviours could be influenced and modified, suggesting that learning could be shaped through stimulus-response associations.

In educational contexts, understanding behaviorism allows educators to apply their knowledge of eliciting certain behaviors through reinforcement or conditioning techniques. This understanding can guide how they manage classroom behavior, structure learning environments, and design interventions to enhance student learning.

While the other options touch on important concepts related to learning, they do not encapsulate Watson’s main contributions specifically to educational practices as effectively as the application of behaviorism. Thus, the recognition of behaviorism’s applicability in education is crucial.