Final answer:
Young Americans of different races spent their leisure time mostly enjoying jazz music, reflecting cultural shifts and the emergence of a new morality during the 1920s and 1950s, which makes 'D) Enjoying jazz music' the correct answer.
Step-by-step explanation:
The question pertains to how young Americans, both black and white, spent their leisure time. Specifically, it seems to be referring to the youthful cultural movements of the 1920s and 1950s, times of significant social change and the emergence of new musical genres that became central components of youth culture. In the 1920s, jazz music became a symbol of the new morality, as young people in urban areas embraced lifestyles and values that were considered more permissive than those of their parents' generation. In the 1950s, rock 'n' roll music functioned in a similar way, with youth embracing the music and its associations with rebellion against adult authority and societal norms.
Given the options presented, the most accurate answer appears to be D) Enjoying jazz music. This choice captures the essence of the leisure activities that both black and white young Americans participated in during the time periods in question, especially considering the popularity of jazz in the 1920s and the shared cultural experiences surrounding music.