this incorrect pleas let me know which correct answer

Random spot checks by a manager to prevent shirking in the workplace is an example of a mixed strategy subgame perfect Nash equilibrium dominant strategy trigger strategyWhich of the following is true? An extensive form representation usually provides more information than a normal form representation of a game A normal form game is most useful for sequential-move games The notion of subgame perfect equilibrium is more useful in analyzing simultaneous games The notion of credible threats makes more sense in simultaneous games