How did nations collectively intensify the conditions of the Great Depression?

The breakdown in economic interdependence led to the inflation of multiple currencies worldwide and reduced international trade.
The raising of tariffs in different countries led to a restriction of trade that caused the Great Depression to last longer.
The League of Nations’ lack of bylaws to handle economic issues provided no relief to nations in need of loans.
The unwillingness of nations to consider deficit spending stifled production and worsened the plight of unemployed workers around the world.

B?