Final answer:
The British naval blockade during World War I led to a significant reduction in U.S. trade with the Central Powers.
Step-by-step explanation:
As a result of the British naval blockade during World War I, U.S. trade with the Central Powers mostly ended. The blockade was a strategy used to prevent war materials and other goods from reaching Germany and its allies. By cutting off supplies, Great Britain hoped to weaken Germany's war effort. Due to the blockade, the United States, which maintained a policy of neutrality for much of the war, found it increasingly difficult to trade with the Central Powers, consequently leading to a significant reduction in trade.