You work as the enterprise exchange administrator at Xxx .The Xxx network is running in a Microsoft Exchange Server 2010 environment.How can you find out about the mailboxes that exceeds 2 GB in size？（）

• A、You must use the Get-MailboxStatistics cmdlet.
• B、You must use the Test-Mailflow cmdlet.
• C、You must use the Get-StoreUsageStatistics.
• D、You must use the Test-ServiceHealth cmdlet.