Answer:
A) Roosevelt did not want the United States to fall behind in military strength
Step-by-step explanation:
As they already knew Germany and USSR were experimenting already with nuclear technology and trying to make new more powerful weapons and bombs, in this case Roosevelt authorized Einstens $6000 to fund experiments to create nuclear chain reactions that would create an atomic bomb that would allow the american army to win the war, and whoever managed to create it first would have the upperhand on winning the war.