C) Jazz.
Jazz is the musical style that epitomized the 1920s. The 1920s is often referred to as the "Jazz Age," as this was a period of great cultural and artistic growth for jazz music. Jazz originated in New Orleans in the late 19th and early 20th centuries and quickly spread throughout the United States, becoming a popular form of entertainment in dance halls and nightclubs. The 1920s saw the emergence of many famous jazz musicians, including Louis Armstrong, Duke Ellington, and Bix Beiderbecke, among others.