Question: Michael Len Williams II  is best known for producing trap beats for several Southern hip hop artists as well as for producing several singles, such as which song by Barbadian recording artist Rihanna from her seventh studio album, "Unapologetic" (2012)?
Sentence (from "Pour It Up"): "Pour It Up" is a song by Barbadian recording artist Rihanna from her seventh studio album, "Unapologetic" (2012).
Relevant evidence: Yes