Which event is an example of irony in macbeth? a. macbeth tries to have banquo and his son murdered so that they will not take his throne b. macbeth vows to find king duncan's murderer when, in fact, macbeth himself has killed the king. c. lady macbeth tells her husband that he has ruined the party after macbeth sees banquo's ghost d. macbeth sees a bloody dagger on his way to kill the king and believesee it is a sign.