Answer: C - A growth in national government activity
Explanation: The Great Depression was the greatest and longest economic recession in modern world history that lasted 10 years. The depression was caused by the stock market crash of 1929 and the Fed's reluctance to increase the money supply. GDP during the Great Depression fell by half, limiting economic movement.
It was the worst economic downturn in US history which led to the second world war, a rise in nationalism, a return to traditional ideology and a growth in national Government activities.