On February 8, 2015, at the 57th Annual Grammy Awards, West walked on stage as Beck was accepting his award for Album of the Year and then walked off stage, making everyone think he was joking around. After the awards show, West stated in an interview that he was not joking and that "Beck needs to respect artistry, he should have given his award to Beyoncé". On February 26, 2015, he publicly apologized to Beck on Twitter.
Try to answer this question if possible (otherwise reply "unanswerable"): What artist's acceptance speech did Kanye interrupt by walking on stage at the 57th Grammys?
Beck