Which of the following functions of DNA polymerase enzymes is true?

• A. DNA polymerase I is required to remove the RNA primer and fill the gap with DNA.
• B. DNA polymerase III is responsible for catalyzing the 5'→3' polymerization of DNA strands during replication.
• C. The main role of DNA polymerase II is in the repair of inner-strand cross-links.
• D. All of the above.