Before this event, the concept of nuclear fission was theoretical and not taken seriously. What was the event?

A. A feasibility study on nuclear power was set up in Manhattan, New York.
B. Albert Einstein and Leo Szilard wrote a letter to Franklin Roosevelt.
C. Hitler's forces invaded Poland, initiating World War II.
D. The Japanese attacked the U.S. naval base at Pearl Harbor, pushing America into a global conflict.



Answer :

Final answer:

Physicists Leo Szilard and Edward Teller reached out to Albert Einstein, who signed a letter warning President Roosevelt about the German nuclear threat, initiating the Manhattan Project.


Explanation:

The event in question is b) Albert Einstein and Leo Szilard writing a letter to Franklin Roosevelt. In 1939, fearing the development of an atomic bomb by Nazi Germany, physicists Leo Szilard and Edward Teller reached out to Albert Einstein, who signed a letter warning President Roosevelt about the German nuclear threat. This event led to the initiation of the Manhattan Project, a program aimed at creating nuclear weapons.


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