Final answer:
The question is about the Chinese Exclusion Act of 1882, a crucial event in US immigration history. It was the first law to prevent a specific ethnic group from immigrating to the US, specifically targeting Chinese labourers, but allowing certain professionals, like students and merchants.
Step-by-step explanation:
The subject of this question is about an important event in US immigration history commonly referred to as the Chinese Exclusion Act of 1882. This act, signed into law by President Chester A. Arthur, was the first law implemented to prevent a specific ethnic group from immigrating to the United States. This law banned skilled and unskilled laborers from China from immigrating but allowed certain professionals like students and merchants to immigrate. This exclusion act remained in place for more than six decades until it was repealed in 1943.
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