A description of natural events that has been proven to be true time after time, without exception.

This describes

A) data.

B) a theory.

C) a conclusion.

D) a law.

The correct option is D.

A natural law refers to a description of natural event that has been proved to be true without exception. Such a law usually generalizes a body of observation but can not explain why the observation occur. An example of a natural law is Newton's law of gravity, he observed that an object thrown up usually come down but can not explain the reason behind this observation.