Which of the following was not an actor/actress on the American television show "Saturday Night Live" in Season 42?

The answer is Tina Fey. Although Tina Fey was a well-known and influential member of the Saturday Night Live (SNL) cast, she was not part of Season 42. Tina Fey was an actor and writer on SNL from 1997 to 2006, but by Season 42, she had moved on to other opportunities, such as creating and starring in the television series "30 Rock." However, her contributions to SNL during her time on the show were significant and helped shape its comedic style.