User blog comment:SayuriDarling/Full first chapter of The Mark of Athena/@comment-184.58.22.209-20120610200321/@comment-5112532-20120611174457

Nah, I think it will be Percy, Jason, Annabeth, and Hazel (or maybe Frank, but I doubt it!)

Annabeth is a girl and Greek.

Percy and Jason because they're the two leaders (both guys, Greek and Roman). And Hazel to balance out the POVs becuase she's Roman and a girl.