Analyses of Molecular Sequences for Study of Evolutionary Relationships Are

Analyses of molecular sequences for study of evolutionary relationships are constrained by ____.

A) the fact that every base in a nucleic acid serves as a separate, independent character for analysis
B) the presence of many genes that have been conserved by evolution
C) the limited number of nucleotide characters, making it difficult to determine whether genetic similarities between species are homoplastic or homologous
D) the usefulness of genes for studying only closely related species that have minor morphological differences
E) nucleic acids that are not directly affected by the developmental or environmental factors that cause nongenetic morphological variations