Which of the Following Statements About the Process of Creating

Which of the following statements about the process of creating a song by setting a new text to an existing melody is true?

A) It results in a song called a contrafactum.
B) It helps ensure that the new words can be easily remembered.
C) It is used in many musical traditions.
D) It is a songwriting technique that has a long history.
E) All of the above are true.