Respuesta :
Answer:
An introductory section that sets up a lengthy text is a prologue.
Explanation:
A prologue is an introduction or a preface of a literary work. It has relevant pieces of information necessary to the reader before starting the novel. This information is presented in a subtle way to keep the reader's attention and even draw them into the story beforehand.
Both the phrase and definition match. Therefore, the answer is Prologue.