Which of the following is/are required for natural selection to occur?
A. The trait must be used or it will no longer be passed down
B. Trait must be inherited from the father not mother
C. The species could produce more offspring than their environment can support
D. Members of the population must have inherited traits that could vary
E. Members must have an equal ability to survive and reproduce

Natural selection is the process by which among various characteristic individuals of a same species, the nature selects the best possible characteristic feature that will help the species to survive the best, and the rest will be curbed to death in order to reduce the population.

Now this natural selection needs some of the criteria to be fulfilled. In an environment where the supply of resources is much more than what is required by the population, there the natural selection doesn't occur. It requires the population to fight for victory to get their food and shelter, which involves the survival of fittest.

And the natural selection can only occur where the individuals are of different characters. Same type of individuals will be equal with each other in each and every forms. So there the survival of fittest won't take place. Variation is needed for natural selection to occur which selects best possible option from the whole pool.