Answer:
a. a strategically planned offensive
b. it gave allied troops a foothold in Europe
Step-by-step explanation:
The D-Day operation was a carefully and strategically well planned operation. Normandy was targeted as the perfect place for this, and lot of troops were sent on the peninsula in order to push back the Germans and have a foothold in Europe. The numbers were on their side, and even though they had lot of losses, they managed to overcome the far fewer Germans. After they managed to secure the coast, more and more troops were coming as a support, and step by step they pushed the Germans back to Germany and out of France, taking the war in their own country.