An affect of transportation improvements on settlements was that

The development in transportation help the settlers reach the place that cannot be reached. It also make the people became more willing to live in a pretty far distance for their workplace, which increase the number of settlements even in places that have lesser amount of job opportunities.

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i believe the correct answer is option b. most eastern european nations joined nato.

though i could be wrong, option d. the eastern european nations were granted complete independence, would be another choice.

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