Final answer:
Social skills training predominately uses observational learning as its basic learning principle, where individuals learn by watching and modeling others' behaviors, although classical and operant conditioning can also play a role indirectly.
Step-by-step explanation:
When discussing social skills training, the basic learning principle primarily utilized is observational learning. This approach is built upon the concept that people can learn new behaviors by watching others, also known as modeling. In contrast to observational learning, classical conditioning involves learning to associate two stimuli to generate a new learned response, while operant conditioning involves learning to associate a behavior with its consequences, reinforcing or discouraging the behavior.
One can find examples of these learning principles in various scenarios. Take for instance, the famous experiments of Pavlov with dogs, which are a classic example of classical conditioning. Or consider B. F. Skinner's work on operant conditioning, where he demonstrated that consequences such as reinforcers or punishers affect the frequency of a behavior. However, for social skills training, modeling after observed behaviors is key. This can lead to cognitive learning, which is especially important in complex social behaviors where nuances and subtleties are involved.
Overall, while social skills training can indirectly involve components of all three learning types, the primary mechanism at play is observational learning, making it the most accurate answer to the question provided.