'Genetic Adaptation' Can Be Said to Have Occurred Only When

'Genetic adaptation' can be said to have occurred only when:

A) the forces of natural selection lead to increases, in the next generation, of the frequency of genes supporting advantageous manifest traits that already existed within the population.
B) there are more individual members of a species than in the previous generation.
C) individuals within a population have each adapted to environmental pressures.
D) the environmental impact of one generation is greater than that of the previous generation.
E) organisms clone themselves to reproduce.