Which of the following is NOT included in Skinner's theories on behavior modification?

Skinner's theories on behavior modification, particularly through operant conditioning, focus on the ways in which behavior can be shaped through reinforcement and consequences. The strategies he identified include positive reinforcement, where desired behaviors are encouraged through rewards such as praise and feedback, as well as negative reinforcement, which involves the removal of unfavorable conditions to increase desirable behaviors.

The correct choice highlights that "negative reinforcement" is traditionally included in Skinner's framework, as it specifically refers to strengthening behavior by removing an aversive stimulus. However, the option that is not part of Skinner's behavior modification theories is associated with the proactive communication of expectations. Therefore, "clearly inform" stands out as not being an explicit component of Skinner's theories, which are more about the consequences of behavior rather than the initial clarifying of behavioral expectations.

In summary, Skinner’s focus on modifying behavior revolves more around reinforcement and feedback mechanisms rather than the clarity of communication regarding desired behaviors.