A)influenced by multiple genes.
B)determined by a single gene locus.
C)a result of different chromosomes producing distinct phenotypes.
D)due to the presence of different alleles, which express the dominant color.
E)due to the blending of several genes.

A)Each bird evolved a deeper, stronger beak as the drought persisted.
B)Each bird's survival was strongly influenced by the depth and strength of its beak as the drought persisted.
C)Each bird that survived the drought produced only offspring with deeper, stronger beaks than seen in the previous generation.
D)The frequency of the strong-beak alleles increased in each bird as the drought persisted.

A)nucleotide variability only.
B)genetic polyploidy only.
C)average heterozygosity only.
D)nucleotide variability, average heterozygosity, and genetic polyploidy.
E)nucleotide variability and average heterozygosity only.