The statement that best explains the graph is : US defense spending declined after world war II but increased as the cold war heated up ( C )
After world war II the United states Government reduced its spending on the US defense system owing to the fact that the war was over, but as the Cold war intensified the need to increase Defense budget was inevitably as the US increased its defense spending to bolster its defenses
Hence we can conclude that The statement that best explains the graph is US defense spending declined after world war II but increased as the cold war heated up.
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