According to the safety valve theory, what would happen when the American frontier was closed would be that the concept of what it meant to be an American would be changed by the influx of immigrants.
The safety valve theory emerged in the US with the Homestad Act of 1862, and its objective was to deal with unemployment due to the immigration concentration that occurred on the east coast of the country.
With the closing of the borders on the east coast, using the theory of the escape valve, there was a government incentive for immigration to the west of the country, where free land and work would be offered.
Therefore, according to the escape valve theory, the colonization of the West would alleviate the unemployment of the East. Through this influx of immigrants to the West came new American ideas of democracy and individualism, impacting the entire nation.
The alternatives to answer this question are as follows:
A. Economic growth would be halted because companies would have no new markets to conquer.
B. Social conflict would increase because citizens would have nowhere to start from scratch.
C. The country's population would quickly overwhelm its natural resources.
D. The concept of what it meant to be an American would be changed by the influx of immigrants.
The correct alternative is the letter D.
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