Which of the following best describes the theory of natural selection?
a the genetic make-up of a population gradually changes from one generation to the next.
b living organisms change over time.
c each species produces many more offspring than can survive long enough to reproduce. the offspring that do survive contain genes that are inherited from the parents.
d there is variation among the members of a species. some of this variation is genetically determined and so can be passed on to future generations.