Final answer:
The U.S. secret program during World War II to develop atomic weapons was called the Manhattan Project.
Step-by-step explanation:
The subject of this question is History.
The secret program that began during World War II by the U.S. to develop atomic weapons is called the Manhattan Project. It was a top-secret research project that involved scientists, engineers, and military personnel working together to build the first atomic bomb.
The name Manhattan Project was chosen because the research initially began under the direction of the U.S. Army Corps of Engineers in Manhattan, New York.
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