What is a scientific theory?

• A. A hypothesis that remains untested.
• B. A simple model used to explain phenomena.
• C. A well-tested concept that explains a wide range of observations.
• D. A casual explanation for a single observation.

Answer: (C)

Think of a scientific theory as a well-supported framework that explains a wide range of observations and experiments. It’s more than just a guess or a single fact: it brings many different findings under a coherent set of ideas and can make predictions about new situations. Because it’s built from extensive evidence and repeated testing, a theory is trusted, though it can be revised if new data emerge. This is why the description “a well-tested concept that explains a wide range of observations” is the best fit.

In contrast, an untested hypothesis is just a tentative statement awaiting evidence, a simple model describes only a specific aspect or a limited situation, and a casual explanation for a single observation lacks the depth and testing that characterize a theory.