Which answer BEST completes the diagram? A) Results of the Civil War Eliminate B) Causes of the German Migration C) Components of the American System D) Features of the Kansas-Nebraska Act

The correct answer is C. componentes of the American System.
The American System is the name given to a plan created by Henry Clay. And the purpose of that plan was to help American Business during a period of difficulty to compete with the British prices. So, with the components: A Tariff, a National Bank and Roads and Canals, the American System would be a way for the US to become independent from Europe.