Operation overlord was the name of the allied invasion of northwestern

Operation Overlord led to the invasion by the Allies of Northwestern France.

Operation Overlord took place on the Normandy beaches of Northwestern France and allowed the Allies to liberate western Europe such as France and to contribute to Nazi defeat.

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The correct answer is Northwestern Europe, in Normandy, France.

Operation Overlord was the name of the Allied invasion of Northwestern Europe, in Normandy, France.  

The military forces created special codes to identify operations during World War II. Operation Overlord was the code name of the operation that was created to invade Normandy in France, in June 1944. The Allied forces, comprised in the mission by the United States, Great Britain, Canada, France, and Poland, liberated that territory that was invaded by the German Army. After that victory, the Allied forces advanced to Berlin.  

to tell the truth it is a mix of the a and d because after the romans argued among themselves outside forces took control however it is mostly d.