The correct answer is - halted Chinese immigration for a period.
The Chinese Exclusion Act of 1882 was a racist act that was restricting people's migration based on their race or ethnicity, in this case the Chinese people that were limited to just 5,000 people per year allowed to migrate to the United States. This halted the Chinese migration in the United States for some time, and if this act did not took place, the demographic picture of the United States nowadays would probably have been much different and the Chinese population would have been one of the most dominant ones.
