Final answer:
In Greek tragedy, the group of dancers and singers who offer commentary and narration in a play is called the Chorus.
Step-by-step explanation:
In Greek tragedy, the group of dancers and singers who comment upon the action of the play is known as the Chorus. The Chorus was a central feature in Greek dramas, providing narration, commentary, and occasionally interacting with the characters, embodying a collective voice. Playwrights like Aeschylus, Sophocles, and Euripides used the Chorus to a varying extent in their works. Aeschylus is known for decreasing the Chorus's prominence in favor of dialogue, while Sophocles integrated the Chorus more deeply into the action of the play. The function and importance of the Chorus evolved throughout the history of Greek theater, reflecting shifts in dramatic style and performance practice.