Epics such as The Mahabharata and the Iliad were passed down as part of an oral tradition. If a story is part of an oral tradition, which of the following must be true?
A. The story was performed from a script for a live audience, but the performance did not always match the script.
B. The text was passed from person to person, who each made revisions to it over time.
C. The author of the poem spoke it aloud to someone who wrote down the words.
D. The poem was passed from person to person by word of mouth without being written down.