What are the four factors that must be present for natural
selection to act upon a population?

im not sure what your questions is about it could be

1) mutation, gene flow, genetic drift, and natural selection

or

2)reproduction, heredity, variation in fitness or organisms, variation in individual characters among members of the population.

Explanation:

post-impressionism is a predominantly french art movement that developed roughly between 1886 and 1905, from the last impressionist exhibition to the birth of fauvism. post-impressionism emerged as a reaction against impressionists' concern for the naturalistic depiction of light and colour.

explanation:

the answer is: metamorphic rocks often show the presence of fossils, also a

hope i

-lavira: )