Answer: C - written records
Explanation:
Archival methods involve the study of historical documents; that is, documents created at some point in the relatively distant past, which may include magazine or journal that will provide us access so that we might not otherwise have to the organizations, individuals, and events of that earlier time
In this case Dr Michael is making use of some records that have been documented earlier for future purposes.
Written records are the main source of information about work that has been undertaken, decisions made and implemented and incidents that have occurred. They provide information about workers' actions in the event of a complaint or disputed decision