what effect do you think the frontier played in american history? How would the closing of the frontier change this?

The closing of the frontier cause a reduction in individualism. The federal government gained more control over the direction of the nation. On the frontier people had to depend on themselves and their neighbors. With the closing of the frontier people had more reliance on assistance of government.

answer: d. joseph james clark​

explanation:

the answer is c, all the other options are things they are known for.

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