The DNA sequences below show DNA segments for four different species. DNA SEQUENCES Species A TGG CAA CGG CAG ATT TAG Species B TGG CTA CGG CAG ATT TAG Species C TGC CTA CGG CTG ATT TAG Species D TGG CTA CTG CTG ATT TAG Scientists sometimes use DNA sequences such as these to determine the relatedness of different species. Which of the following is a necessary condition for scientists to use DNA sequences in this way?
