Can I downgrade my OEM version of Windows Vista Business to Windows XP Professional?

The Problem:-
Can I downgrade my OEM version of Windows Vista Business to Windows XP Professional?

Resolution:-

Yes,you can.According to Microsoft:-OEM downgrade rights for desktop PC operating systems apply to Windows Vista Business and Windows Vista Ultimate as stated in the License Terms. Please note, OEM downgrade versions of Windows Vista Business and Windows Vista Ultimate are limited to Windows XP Professional (including Windows XP Tablet PC Edition and Windows XP x64 Edition).