The U.S. government supported the establishment of the Selective Service Act largely to
O Remedy the fact that too few men were signing up for the military.
O Incorporate women and African Americans into the war effort.
Justify the enormous war budget he was proposing to Congress.
O Demonstrate his resolute support for the war effort.

The U.S. government supported the Selective Service Act to address low voluntary enlistment rates and justify the war budget proposed to Congress, fearing insufficient army growth and concerns about haphazard enlistment.

Explanation:

The U.S. government supported the establishment of the Selective Service Act largely to:

Remedy the fact that too few men were signing up for the military.
Justify the enormous war budget he was proposing to Congress.

Congress believed that volunteer enlistment alone would not be sufficient to increase the size of the army, and there were concerns that men with vital industrial skills might join the military voluntarily, affecting the home front. Therefore, the draft was seen as necessary to ensure a sufficient military force.

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