Final answer:
The body of water over which American military forces conducted the D-Day Invasion during World War II is the English Channel.
Step-by-step explanation:
The body of water over which American military forces conducted the D-Day Invasion during World War II is the English Channel. The invasion took place on June 6, 1944, and it was a major turning point in the war. The English Channel is a narrow stretch of water that separates southern England from northern France.
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