Questions: Which of the following best defines a scientific law? A An 'if, then' statement that can be tested by science. B A model used to explain how or why a phenomenon occurs. C A unifying concept; often a mathematical description of the way in which a natural phenomenon occurs. D A new occurence that cannot be explained using what is currently scientifically known. E Something that is known to be consistent with reality; that which has not been falsified.

The answer is the third one (C): A unifying concept; often a mathematical description of the way in which a natural phenomenon occurs.

Explanation for each option:

A. An 'if, then' statement that can be tested by science.

• This describes a hypothesis rather than a scientific law. Hypotheses are specific predictions that can be tested through experiments and observations.

B. A model used to explain how or why a phenomenon occurs.

• This describes a scientific theory. Theories provide explanations for phenomena and are supported by a large body of evidence.

C. A unifying concept; often a mathematical description of the way in which a natural phenomenon occurs.

• This correctly defines a scientific law. Scientific laws describe consistent and universal relationships observed in nature, often expressed mathematically.

D. A new occurrence that cannot be explained using what is currently scientifically known.

• This describes an anomaly or a new discovery, not a scientific law.

E. Something that is known to be consistent with reality; that which has not been falsified.

• This is a general description of scientific knowledge but does not specifically define a scientific law.

Summary: A scientific law is a unifying concept that often provides a mathematical description of natural phenomena, making option C the correct definition.