Answer:
The act that authorized a draft of young men for military service in Europe is called the Selective Service Act.
Step-by-step explanation:
On May 18th, 1917, Congress passed the Selective Service Act, which authorized the federal government to temporarily expand the military through conscription. The Act required all men from ages 21 to 45 to register for military service. Of the total US troops that were sent to Europe during World War I, 2.8 million of them were drafted by the Selective Service Act, while 2 million others had volunteered.