Scientists use dna sequencing to understand relationships among life on earth. the chart illustrates differences between five species and humans. although the dna sequence of each may vary, all but one statement concerning the organisms is true. a) the same nitrogen bases are found in all six organisms. b) the steps in proteins synthesis are identical in all six organisms. c) the dna sequences may vary but the amino acid sequences are identical. d) the process of producing new dna, or replication, is identical in each.