The concept of evolution by way of natural selection is a central tenet in biology that has been tested in numerous ways by many scientists. Evolution by way of natural selection is most likely which type of concept?

A. an explanation of phenomena that can be accepted as true because it is supported by repeated observations and experimentation

B. a likelihood based on the chance that a particular event will or will not occur during an experiment

C. a testable explanation or answer to a scientific question based on prior knowledge or research

D. a statement of fact that is accepted as true because it has always been observed to be true through observations and experimentation