Which event abruptly ended the prosperity of the Roaring Twenties?

The Wall Street Crash of 1929 is the pivotal event that abruptly ended the prosperity of the Roaring Twenties. This period, characterized by economic growth, cultural blossoming, and overall social change, came to a sudden halt as a result of the stock market crash that occurred in October 1929. The crash led to a significant loss of wealth and confidence among investors and consumers, leading to widespread economic turmoil.

The aftermath of the crash activated a chain reaction that culminated in the Great Depression, greatly impacting every aspect of American life, including employment, banking, and international trade. While other options like the Dust Bowl and the New Deal had significant repercussions for American society and economy, they did not directly trigger the immediate cessation of the economic boom that defined the 1920s in the same way the Wall Street Crash did. World War I, conversely, had already concluded, and its effects were felt prior to this period of prosperity. Thus, the Wall Street Crash stands out as the key event that marked the end of the Roaring Twenties' economic boom.