Which of the following is the major role of the 3′→5′ exonuclease activity of DNA polymerases?

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The 3′→5′ exonuclease activity of DNA polymerases is primarily responsible for proofreading, which involves removing mismatched nucleotides to ensure the accuracy of DNA replication.  The main enzymatic activity of DNA polymerases is the 5′ → 3′ synthetic activity. However, DNA polymerases possess two additional activities of importance for both replication and repair. These additional activities include a 5′ → 3′ exonuclease function and a 3′ → 5′ exonuclease function. The 3′ → 5′ exonuclease function is utilized during replication to allow DNA polymerase to remove mismatched bases and is referred to as the proof-reading activity of DNA polymerase. It is possible (but rare) for DNA polymerases to incorporate an incorrect base during replication. These mismatched bases are recognized by the polymerase immediately due to the lack of Watson-Crick base-pairing. The mismatched base is then removed by the 3′ → 5′ exonuclease activity and the correct base inserted prior to progression of replication.

Which of the Following Is the Major Role of the 3′→5′