This is, surprisingly, another variety of the same question, but it is tricky. The reason is that you want to show that you are a leader and a great team player, so when answering this question be cautious to use an example that does not suggest that you failed to “step up”—i.e., failed to live up to the expectations of those around you. Much better would be to use an example where you were unsure at first whether X was the right course of action, but upon further contemplation, decided that it was—and then did X to the best of your ability.