Use data-at-rest scans to locate and identify sensitive data. This option is the best DLP consideration for addressing the sensitive data on the file servers. Data-at-rest scans are performed on data that is stored on a device or a network, such as file servers, and can help identify and classify sensitive data based on predefined policies or rules. The other options are not relevant for this scenario, as they either deal with data in transit (network DLP appliances), data in use (endpoint DLP agents), or cloud-based data (CASB device).