Which of the following statements about the correction of errors in DNA replication is/are correct? Choose all that apply.
a) 3'-5' exonuclease activity results in 100-fold reduction in error rates.
b) DNA polymerases have 3'-5' exonuclease activity.
c) 3'-5' exonuclease activity depends on the methylation state of the DNA strand.
d) E. coli does not methylate DNA in a particular region once replication has occurred in that region.
e) The methylation sequence in E. coli recognized by a particular methylase is 5'-GATC-3'.
