How can an administrator make the 'Search Vaults' button in Outlook available to users?

How can an administrator make the ‘Search Vaults’ button in Outlook available to users?

How can an administrator make the ‘Search Vaults’ button in Outlook available to users?
A . use the Exchange desktop policy, ‘Options’ tab
B . use the Search Provisioning Group
C . use the Exchange mailbox policy, ‘Options’ tab
D . use the IMAP Provisioning Group

Answer: D