Answer:
Option D
Explanation:
B and C are just totally incorrect. A is only partially correct because the Compromise of 1850 was the only one to enforce the Fugitive Slave law, however both the Compromise of 1850 and the Kansas-Nebraska act made popular soveriegnity the method of determining whether a territory would be a slave state or a free state. This was also one of the main causes of the civil war.
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