You have an Exchange Server 2010 organization that contains 20 mailbox databases. You configure each database to retain all deleted items for 30 days.You need to ensure that all items that pass the retention period are permanently deleted daily between 02：00 and 06：00. Which cmdlet should you use？（）

• A、Set-MailboxDatabase
• B、Set-MailboxServer
• C、Set-OrganizationConfig
• D、Set-RetentionPolicy