Final answer:
The Swing Era, part of the Jazz Age, was significant due to its major impact on dance and American culture, where jazz thrived in venues like Harlem's Cotton Club and influenced social norms and future musical genres.
Step-by-step explanation:
The Swing Era was unique in American culture because it was a major cultural and dance phenomenon. This period, often associated with the Jazz Age or the Roaring Twenties, saw a tremendous growth in jazz's popularity. Jazz music, deeply rooted in African American communities, emerged from a blend of musical traditions including blues and ragtime. It quickly became a symbol of the era, embodying the liberation and the vibrant culture of the time.
Iconic venues like Harlem's Cotton Club hosted legendary jazz artists like Duke Ellington and Cab Calloway, drawing in crowds of young, fashionable people - known as flappers and sheiks - who embraced the music and the accompanying dance styles. In this environment, social norms were tested, and people indulged in a lifestyle that represented a break from the past. The influence of jazz extended beyond just music, as it had a lasting impact on future genres and the broader American culture.
The correct answer to your question is c) It was a major cultural and dance phenomenon.