Step 1: Understanding the Concept:
The question refers to the most severe worldwide economic downturn of the 20th century, widely known as the Great Depression.
Step 2: Detailed Explanation:
The Great Depression was a global economic crisis that began with the Wall Street stock market crash in the United States in October 1929. The crash signaled the beginning of a decade-long period of high unemployment, poverty, low profits, deflation, and falling trade. The period 1929-1930 marks the onset of this catastrophic event. The other periods listed are associated with different economic events, but not the Great Depression.
Step 3: Final Answer:
The Global Economic Depression, or the Great Depression, began in 1929. Therefore, the period 1929-1930 correctly identifies its start. Option (A) is correct.