Answer:
The US entry into the First World War frustrated Germany's strategy of weakening the countries of the Triple Entente (Russia, United Kingdom and France).
Step-by-step explanation:
When the Russians came out of the First World War, the Entente bloc became very weak, so Germany and its ally were able to make much headway. With the exit of Russia, the United Kingdom and France were very worn out and the chances of defeat were increasing.
On April 6, 1917, the United States declared war on the Germans and their allies. A large volume of soldiers, tanks, ships and warplanes were used to ensure that the Entente victory was secured. The arrival of all these things strengthened the Entente and frustrated the plans of Germany to advance before their enemies. In a short time, the German and Austrian troops were defeated. In November 1918, the armistice of Compiègne was successful in the withdrawal of the Germans and the rapid victory of the Triple Entente.