Which song was written and produced by Rihanna and Verse Simmonds on Rihanna's fifth studio album "Loud?"
Verse Simmonds:  The duo has since co-written and produced tracks such as "Man Down" by Rihanna and "Who Gon Stop Me" by Kanye West and Jay-Z, both of which charted prominently on "Billboard". Man Down (song): "Man Down" is a song by Barbadian singer Rihanna from her fifth studio album, "Loud" (2010).
Man Down