Here's why:
* Call and response is a musical form where a leader (the "call") presents a musical phrase, and a group (the "response") answers back.
* Improvisation is a key element of call and response, but it's not always the primary response. Sometimes the response is a pre-arranged melody or rhythm.
Examples:
* Gospel music: The soloist "calls" with a phrase, and the choir responds with the same phrase, often adding embellishments.
* Traditional African music: A lead singer might call a phrase, and the other singers answer with a pre-determined pattern.
* Jazz: A soloist might present a melody, and other musicians improvise responses, creating a dialog of musical ideas.
In conclusion: While improvisation is often involved in call and response, it's not the sole defining factor. The response can be either improvised or pre-arranged.