Answer:
The war fostered influenza in the crowded conditions of military camps in the United States and in the trenches of the Western Front in Europe. The virus traveled with military personnel from camp to camp and across the Atlantic, and at the height of the American military involvement in the war, September-November 1918, influenza and pneumonia sickened 20%-40% of U.S. Army and Navy personnel. These high morbidity rates interfered with induction and training schedules in the United States and rendered hundreds of thousands of military personnel non-effective.
Answer: A encouraging voter registration
Explanation: I just got it wrong on apex from the person who gave the previous answer
