What Technique Was Used by the Incas to Control the Actions

What technique was used by the Incas to control the actions of the people they had conquered?

A) They enslaved women and children to avoid attack.
B) They held important members of the royal family hostage.
C) They kidnapped religious images belonging to the defeated peoples.
D) They kept the defeated peoples in walled compounds at night.
E) They chanted insulting and humiliating songs in the presence of defeated leaders.