It's 2008, which is one of the greatest NCAAB teams ever.
The 2008 team had the 3rd highest adjusted efficiency margin of any team in the KenPom era (2002-2023), with the only two other teams better than it having lost in the tournament (2015 UK, 2021 Gonzaga).
2008 also had the highest SRS of any team in KU basketball history since 1949 (when it is first measured on BRef:
https://www.sports-reference.com/cbb/schools/kansas/).