What characterizes the "call and response" format in choral music?

The characterizing feature of the "call and response" format in choral music is its structure, where an initial vocal phrase or musical motif (the "call") is presented by one singer or group, and is then followed by a complementary phrase or response from another singer or group. This back-and-forth interaction creates a dynamic and engaging musical dialogue, allowing for the expression of different musical ideas while providing a framework for participation and collaboration among the singers.

In this context, the call and response format is often used in various musical traditions, enhancing both the individual contributions and the cohesive sound of the choir as a whole. This collaborative form fosters a sense of community and engagement within the music, making it a popular technique in many genres, especially in gospel, folk music, and some contemporary styles.

The other options describe different musical concepts: a repeated phrase refers to motifs but does not involve the interactive aspect; a continuous song implies no breaks or responses; and harmony involving multiple voices pertains to vocal layering without the back-and-forth exchange that defines call and response. Thus, the essence of the call and response is its unique interactive exchange, which is accurately captured in the selected answer.