How did the government encourage citizens to join in the war effect answers?

The United States home front during World War I saw a systematic mobilization of the country's entire population and economy to produce the soldiers, food supplies, ammunitions and money necessary to win the war. Although the United States entered the war in April 1917, there had been very little planning, or even recognition of the problems that Great Britain and the other Allies had to solve on their own home fronts. As a result, the level of confusion was high in the first 12 months, before efficiency took control.

The war came in the midst of the Progressive Era, when efficiency and expertise were highly valued. Therefore, both individual states and the federal government established a multitude of temporary agencies to bring together the expertise necessary to redirect the economy and society into the production of munitions and food needed for the war, as well as the circulation of beliefs and ideals in order to motivate the people.

the answer might be either a or c. can't be too sure , because i searched the web, but no valid answers came through.