How does "round" function in choral music?

"Round" in choral music is a specific type of composition characterized by multiple voices singing the same melody but starting at different times. This technique creates a layered harmonic effect, as each voice enters progressively, resulting in a rich tapestry of sound. The most famous example of a round is "Frère Jacques," where one group begins singing, followed by another group joining in at a later time.

The other options do not accurately capture the essence of what defines a round. Singing a sequence of notes in ascending order refers more to melodic scales or passages rather than the structural interaction between voices seen in a round. A solo performance accompanied by a choir describes a different format entirely, emphasizing a soloist rather than the interplay between multiple voices. Finally, a song performed without any accompaniment refers to unaccompanied singing, which can take many forms but does not specifically denote the staggered entry characteristic of rounds. Thus, the first choice encapsulates the concept of a round effectively, highlighting the unique harmony that arises from staggered entrances.