With Few Exceptions, We Cannot Use Observable Traits to Measure

Multiple Choice

With few exceptions, we cannot use observable traits to measure the amount of genetic variation in populations because:

A) observable traits do not vary enough among individuals to measure.
B) we cannot identify enough observable traits to be useful, even if they could be measured.
C) many traits are encoded by large numbers of genes.
D) observable traits are products of the environment as well as the genome.
E) many traits are encoded by large numbers of genes, and observable traits are products of the environment as well as the genotype.