Which type of behavior can only be observed by the individual performing it?

The correct answer is private behavior, which is behavior that can only be observed by the individual performing it. This type of behavior includes internal states and activities such as thoughts, feelings, and sensations that are not accessible to others. For instance, when someone feels anxious or is thinking about a personal problem, these experiences are private and cannot be observed directly by anyone else.

In contrast, public behaviors can be observed by others, making them a different category entirely. The distinction is important in behavioral analysis for understanding how certain behaviors impact individuals internally and how those feelings or thoughts may influence public actions. Meanwhile, response and operant behaviors can refer to actions that result from environmental stimuli and consequences, which are typically observable by others. This emphasizes the unique nature of private behavior, highlighting its subjective and introspective qualities.