The increasing popularity of spectator sports and popular musical acts in American cities during the late 19th and early 20th centuries is most attributable to which of the following factors? A. Temperance movements were highly successful in reducing public alcohol consumption.

B. Many Americans embraced the ideals promoted by Eastern European cultures.

C. Middle-class Americans had more free time and money to enjoy leisure activities.

D. African Americans began attending mixed-race entertainment venues in large numbers.