[VIDEO] 130810 f(x) = Mentioned in Infinity Challenge Cut On August 10, 2013 By hearteumiIn f(Amber), f(Krystal), f(Luna), f(Sulli), f(Victoria), Videos Yoo Jaesuk basically asked them to say the names of all f(x) members as part of a quiz. Share this: Click to share on X (Opens in new window) X Click to share on Facebook (Opens in new window) Facebook Click to share on Tumblr (Opens in new window) Tumblr More Click to share on Pinterest (Opens in new window) Pinterest Click to share on Pocket (Opens in new window) Pocket Click to share on WhatsApp (Opens in new window) WhatsApp Like Loading... Related