You have a Microsoft Office SharePoint Server 2007 Service Pack 2 (SP2) server farm. You upgrade
the server farm to SharePoint server 2010. You open a SharePoint site and discover that you cannot
select the Visual Upgrade option. You need to ensure that you can perform a visual upgrade of the
SharePoint site. What should you do?

A.
Run the upgrade-spcontentdatabase cmdtet.

B.
Run psconfig.exe and specify the -cmd parameter.

C.
Run stsadm.exe and specify the setpropertcy operation.

D.
Run stsadm.exe and specify the preupgradecheck operation.

Explanation:

UpdateUserExperience parameter Determines whether the content databases should upgrade to
the latest user interface. By default, the user interface will not change during upgrade.
http://technet.microsoft.com/en-us/library/ff607813.aspx :