Why is phenotypic variation necessary for natural selection

Phenotypic variation is the variation which appears in the phenotype or morphology of the organism. Natural selection is the mechanism of evolution in which the adapated organism to the environment is selected or highly favoured during the course of evolution.

A phenotype is the results of the genetic change which to be established in a population has to be passed on to the generation.

Since variation in phenotypic traits allows the organism to leave indifferent circumstances therefore phenotypic variation proves essential condition to natural selection.

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".

i believe it is c: genes for body color and wing size are inherited separately from each parent.