Read the draft passage. The first paragraph introduces a data ethics policy prepared by a research institute. The policy lists three steps required for temporary analysis files. In the second paragraph, the writer includes "Project teams are required to remove personal identifiers before analysis, to restrict access during review; and to destroy temporary files after approval." The final section explains who verifies compliance. The data ethics policy uses edited American English, so the final item is preceded by both a serial comma and the conjunction. Which complete revision gives the data ethics policy a clear simple series?