Which US President was NOT a member of Delta Kappa Epsilon?

Bill Clinton is the correct answer because he is not known to be a member of Delta Kappa Epsilon (DKE). While the other three presidents—Rutherford B. Hayes, George H.W. Bush, and Theodore Roosevelt—were all members of the fraternity during their time in college, Clinton's educational background does not link him to DKE. Clinton attended Georgetown University for his undergraduate studies, and while he was involved in various student organizations, he was not affiliated with Delta Kappa Epsilon. This distinction highlights the fraternity’s historical connections to several notable political figures, while Clinton's path diverged from that tradition.