What has become the default graphical user interface for Oracle Solaris 11 desktop operation?

The Solaris 11 release in November 2011 only contains GNOME as a full desktop.

Incorrect:

Not A: The Common Desktop Environment (CDE) is a desktop environment for Unix and OpenVMS, based on the Motif widget toolkit. For a long period, it was the "classic" Unix desktop associated with commercial Unix workstations. After a long history as proprietary software, it was released as free software on 6 August 2012, under the GNU Lesser General Public License.