A Trigger Strategy Is

A trigger strategy is:

A) Used to obtain a higher payoff by committing to a strategy before a rival can commit to a strategy.
B) A strategy that selects the worst payoff from among the best payoffs.
C) A move made by a player in response to an unanticipated move by a rival.
D) A strategy that is neither strictly- nor weakly-dominant.
E) Both a and c are correct.