What is characterized by a set of related concepts and definitions to explain phenomena?

The correct choice, which is theory, is distinguished by its function in the realm of research and explanation of phenomena. A theory serves as a well-substantiated principle that is derived from a body of evidence, demonstrating how and why certain aspects of the world function. It comprises a cohesive structure of concepts and definitions that interrelate to form a comprehensive explanation of specific phenomena, making it essential for guiding research and practice in fields such as nursing.

Theories are developed over time through rigorous testing, evaluation, and refinement, which allows them to offer reliable frameworks for understanding complex issues. In nursing, theories help to inform practice, provide a basis for research, and serve as a guideline for the development of effective interventions.

While other options such as framework, model, and paradigm have their own significance, they do not encapsulate the broad and systematic nature that a theory provides. A framework organizes knowledge and provides structure for understanding a specific topic, but it may lack the explanatory power of a full theory. A model often represents a simplified version of reality to illustrate particular concepts or relationships, while a paradigm encompasses a broader worldview or belief system that influences how research is conducted and interpreted. Thus, among the listed options, theory is the most accurate response for defining a