premise: Variations on a Korean Folk Song is a major musical piece written for concert band by John Barnes Chance in 1965. As the name implies, "Variations" consists of a set of variations on the Korean folk song "Arirang", which the composer heard while in South Korea with the U.S. Army in the late 1950s. In 1966 the piece was awarded the American Bandmasters Association's Ostwald Award.
hypothesis: Variations on a Korean Folk Song was written in the 20th century.
reason: It's definitely correct because it was written in 1965, which is in the 20th century. I don't think the system understands what it means for something to be produced/created in a certain century so it always gets that type of question wrong.