Which of the following statements about sequence proofreading during DNA replication is false?
(a) The exonuclease activity is in a different domain of the DNA polymerase.
(b) The exonuclease activity cleaves DNA in the 5'-to-3' direction.
(c) The DNA proofreading activity occurs concomitantly with strand elongation.
(d) If an incorrect base is added, it is "unpaired" before removal.
Answer: B