The interstate highway system was authorized by the federal-aid highway act of 1956 for the primary purpose of a) allowing people to live further from their places of work. b) encouraging more people to settle sparsely populated regions. c) strengthen our national defense by creating an easier means of transporting people and goods in an emergency. d) building a network of roads that would to send work crews around the country to ease the effects of the great depression.

C) Helping strengthen our national defense by creating an easier means of transporting people and goods in an emergency.

Explanation:

The Interstate Highway System was created by the Federal-Aid Highway Act of 1956. The purpose of this bill was to eliminate unsafe roads, inefficient routes, traffic jams and other problems of transcontinental travel. The reason why President Eisenhower was concerned about the situation of the roads was because he wanted evacuation to be as efficient as possible in the case of atomic attack to cities. Therefore, one of the main aims of this bill was to strengthen our national defense by creating an easier means of transporting people and goods in an emergency.

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