When Clausen and colleagues grew genetically identical individuals of the yarrow plant at different elevations,the results are shown in the accompanying figure.This observation verifies that ________.

A) yarrow plants mutate quickly when grown in different environments
B) the genotypes of yarrow plants has nothing to do with how tall these plants grow
C) yarrow plants grow taller at lower elevations and shorter at higher elevations regardless of their genotype
D) the genotypes of yarrow plants interacts with environmental influences to produce the phenotype