Final answer:
The establishment of committees of vigilance in gold-rush California
Step-by-step explanation:
The subject of this question is History.
During the gold rush in California, the establishment of committees of vigilance is the answer. Option A states that these committees enforced laws as they saw fit and expelled non-white miners. These committees were formed by the white settlers to maintain law and order during the chaotic gold rush period. They often took matters into their own hands and sometimes acted in discriminatory ways, making decisions based on their own judgments rather than the official legal system.
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