Answer: D
Explanation:
Black Tuesday happened in 1929, the Dawes Plan happened in 1924, and the Dust Bowl happened in 1930-1936, but the Dust Bowl was an environmental issue, not a trade issue.
The Hawley-Smoot Tariff Act raised previously high tariffs on foreign imports relating to agriculture and was put into effect on March 13, 1930. While it was thought to help farmers grow food during the Depression Era, it actually raised the prices on food and helped poverty be more destructive.
