Company.com has employed you as their Exchange administrator.The Company.com network contains Mailbox servers that are configured to run either Exchange Server 2007 or Exchange Server 2010.During the course of the week you receive an instruction from the CIO to ensure that all e-mail messages stored for more than 90 days in the Inbox folder of clients be deleted. What should you do？（）

• A、Your best option would be to create a new retention policy.
• B、Your best option would be to create a new message classification.
• C、Your best option would be to create new managed content settings.
• D、Your best option would be to create a new managed custom folder.