all top 6 nations are sending, c or d teams.
I don't think so.
This year, as well as each olympic year, the situation is a bit different, the rosters are weaker than in non-olympic years.
But still, Russia has definitely a B team this year with many 'A' team players. (Ovechkin, Malkin, Kuznetsov, Burmistrov, Kulemin, Anisimov, Belov, Bobrovsky + B players like Medvedev, Shirokov, Tikhonov, Orlov, Zaripov) and they are without Kovalchuk and Radulov who are injured. The Czechs have Jagr, Sobotka, Hertl, Cervenka, Novotny, Hudler, Rolinek, Polak, Kindl, and goaltender Salak, who are all 'A' or near-'A'-team material. The rest is something from B team and something from C team I believe.
Sweden has almost a complete B/C team. Finland too. Don't forget about O.Jokinen, Rask, Karalahti, Immonen, Kontiola and Komarov, who are 'A' or near-'A'-team level.