Final answer:
Spheres of influence in China impacted American foreign policy by leading to the proposal of an Open Door policy.
Step-by-step explanation:
American foreign policy was impacted by spheres of influence in China as it caused America to propose a policy giving all nations equal access to China's markets. The concept of spheres of influence divided China into different regions controlled by European powers and America feared being left out of the economic opportunities in China. To counter this, America proposed the Open Door policy, which aimed to ensure equal access to China's markets for all nations, including the United States.
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