Final answer:
The economic boom of the 1920s in the United States was driven by the promotion of mass production and consumerism, which made goods more affordable and created a widespread consumer culture that spurred the growth of businesses and the stock market.
Step-by-step explanation:
The changes in business practices during the 1920s contributed to the economic explosion in the United States by encouraging mass production and consumerism. The era saw businesses thrive with the proliferation of mass-produced goods which were marketed and distributed across a burgeoning national consumer market. This period, highlighted by the popularity of goods such as automobiles and radios due to their reduced costs, allowed more Americans to participate in the purchasing frenzy. Industrialization, which had been growing since the late 19th century, made goods more affordable and available for the middle class, further fueling the consumer culture. The stock market's meteoric rise was both a reflection of and a contributor to this economic boom, albeit one that would sow the seeds for the eventual crash at the end of the decade.