Final answer:
During the Harding administration, labor unions faced challenges and declines, including difficulty in organizing immigrant workers and exclusion of African Americans from many unions.
Step-by-step explanation:
During the Harding administration, labor unions faced challenges and declines. One reason for this decline was the difficulty of organizing immigrant workers due to language barriers and their willingness to work in poor conditions. Additionally, many unions excluded African Americans, reducing their favorability. Overall, the labor movement experienced setbacks during this time.