Final answer:
Most mistakes during DNA replication are corrected by DNA polymerase's proofreading function, which reads and corrects mismatched nucleotides. The correct answer is that proofreading corrects most of the mistakes by removing mismatched nucleotides and replacing them with the correct ones.
Step-by-step explanation:
When mistakes occur in DNA replication, most of the mistakes are promptly corrected by a function of DNA polymerases known as proofreading. During proofreading, the DNA polymerase reads the newly added base, ensuring that it is complementary to the corresponding base in the template strand. If an incorrect base has been added, the enzyme will use its exonuclease action to make a cut at the phosphodiester bond, release the wrong nucleotide, and then add the correct one instead. Consequently, the correct answer to the question is 'Proofreading corrects most of the mistakes by removing and replacing the mismatched nucleotides.'
Furthermore, there are mismatch repair mechanisms that also contribute to correcting errors that were not recognized during the proofreading step. These mechanisms identify and excise incorrectly added nucleotides that have been mismatched and then replace them with the correct base. Thus, while DNA replication is a highly accurate process, the cell has evolved several repair mechanisms to minimize the number of mutations that persist.