I believe the answer is C. It would have the most economic effect.
The US foreign policy distanced it from Cuba, in not only diplomatic relations , but trade, etc.
<span>May 31, 2016 - The latest spending figures confirm an ongoing trend: Americans are buying big ticket items like refrigerators, roofs, cars and televisions.</span><span>
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The main reason why the border states did not secede in 1860-1862 was because they were concerned with the large amount of military coercion that was taking place in the South, and they felt that the South was ultimately unjustified in removing itself from the Union.