Honestly, Those exams depend both on power and ninjas that you have, if you don't have any sort of overpowered ninjas I'd recommend using Lightning Main, Anbu Itachi, Sasuke (full breakthrough) and iruka. Seems to be one of the best f2p lightning main blitz teams and has high combo, but some of the levels are just not possible to pass if your power is too low. Any lightning main blitz would be the best option since tanking wouldn't work that well and they have low defense.

Position1: LM, Position2: Iruka, Position3: anbu itachi, Position4: Sasuke

You'd use the talents lightning blade as mystery, Calm Mind standard, Chase repulse to knockdown, Killing Intent and root of the warrior. Golden serpent is best for the lineup but the regular white purple one can work as well just not as big a combo.