Final answer:
The beginning of the Great Depression was triggered by the stock market crash on October 24, 1929, which exposed foundational weaknesses in the economy and led to widespread financial turmoil and unemployment.
Step-by-step explanation:
The event that triggered the beginning of the Great Depression was the massive stock market crash on October 24, 1929. This economic calamity marked the end of the Roaring Twenties and ushered in an era of widespread financial hardship for most Americans. While the stock market crash itself was not the sole cause of the Great Depression, it served as a catalytic event that exposed inherent weaknesses within the economy and the banking system. The crash caused a consumer panic and revealed the shaky foundation upon which much of the economic growth of the 1920s had been built, including a reliance on easy credit and speculative investment practices. As bad debts were called in, many American banks demanded repayment of the European loans. When those funds could not materialize, both foreign and domestic businesses shut down, leading to soaring unemployment rates and austerity measures that further contracted the economy. Consequently, banks closed, millions of jobs were lost, and the country's gross national product declined significantly.