What reason does macbeth give for ordering the murder of banquo and his son?
a. he wants to prevent banquo's son from becoming king as the witches predicted. 
b. he thinks that banquo will try to kill him to gain the crown for his family. c. he is offended that banquo has not come to the castle to pay him respect as the new king. 
d. he believes that banquo and his son are guilty of many crimes and should be punished.