Judged by the average number of nucleotide-pair differences per 1000 nucleotide pairs, which of the following pairs show the highest difference?

A) The genomes of S. cerevisiae and M. musculus
B) The genomes of two different E. coli strains
C) The ribosomal RNA genes from human and E. coli
D) The transfer RNA genes in a human and M. musculus
E) The genomes of two humans