What is the definition of psychology?

The definition of psychology as the scientific study of behavior and mental processes captures the field's essence by emphasizing both observable actions and internal experiences. This dual focus allows psychologists to explore a wide range of topics, from the biological underpinnings of behavior to the complex interplay of thought processes, emotions, and societal influences. It illustrates that psychology is not just about how individuals interact with one another, as suggested by the first choice, nor is it limited to evaluating cognitive functions or analyzing social structures.

Option two encompasses various subfields like cognitive psychology, which looks at mental processes such as perception and memory, as well as behavioral psychology, which emphasizes observable behaviors. By acknowledging the scientific methodology central to psychology, the definition ensures that findings are empirical, replicable, and subjected to rigorous testing. This foundation is crucial for establishing psychological principles that can be applied in real-world settings, making option two the most comprehensive and accurate description of psychology.