It was a tough choice since all four teams have 4-5 members I know of with their strengths and abilities. But I would probably go with either Team A 或者 Team C since both teams have strong fighters and some has great strategies to use, especially since Team A has Erza, Luffy, Itachi, Lelouch and Eucliwood on the team while Team C has Rias, Roy, Rin, Suiginotu and Black 星, 星级 on their team.
Team A. They've got such strong characters. Luffy, Erza, Itachi, Levi... and then a mastermind like Lelouch and a psycho like Yuno. That team is marvelous, lol.