What is the definition of psychology?

The definition of psychology is best captured by the description as the scientific study of behavior and mental processes. This definition highlights two core components of psychology: behavior, which encompasses all observable actions and reactions of individuals, and mental processes, which refer to internal experiences such as thoughts, feelings, and perceptions.

By emphasizing the scientific aspect, this definition indicates that psychology employs systematic methods to gather data, formulate theories, and test hypotheses regarding human and animal behavior. This approach differentiates psychology from other fields that may not rely on empirical evidence or scientific methodologies.

The other choices focus on different domains. The examination of societal structures and their impact relates more to sociology or social psychology, where the focus is on group behavior and social influences. Analyses of historical events and their influences would fall under history or historiography, concentrating on the past rather than present behaviors or mental states. Evaluating biological environments on behavior emphasizes biological psychology but is too narrow to encompass the full breadth of psychological study, which includes a variety of perspectives and approaches, not just biological factors.