What term describes a reasoned explanation for a scientific event?

A theory is a well-substantiated explanation for some aspect of the natural world that incorporates facts, laws, observations, and tested hypotheses. It is developed through a rigorous process that includes extensive testing and validation over time, differentiating it from simpler concepts such as hypotheses, which are often preliminary guesses or starting points for investigation.

Theories not only explain existing observations but can also predict new phenomena, making them powerful tools in the scientific method. For instance, the theory of evolution explains the variety of life on Earth and can predict outcomes based on genetic principles. By contrast, while scientific principles and research elements are essential components of scientific inquiry, they do not serve the same comprehensive explanatory role as a theory.