Which enzyme has proofreading and repair functions during DNA replication?

• A. DNA polymerase
• B. Ligase
• C. Helicase
• D. Primase

Answer: (A)

Verified step by step guidance

1. Understand the role of each enzyme listed in the options during DNA replication.
2. DNA polymerase is responsible for adding nucleotides to the growing DNA strand and has proofreading abilities to correct errors.
3. Ligase is involved in joining Okazaki fragments on the lagging strand but does not have proofreading functions.
4. Helicase unwinds the DNA double helix but does not participate in proofreading or repair.
5. Primase synthesizes RNA primers needed for DNA polymerase to begin replication but does not have proofreading capabilities.