It's D. There were no islands of any consequence in Europe except Sicily. Europe was a different kind of war that that of the Pacific.
Europe was a war fought by the army in Russia and the Air force (mainly) in Great Britain.
The war in the Pacific, on the other hand, was really a war fought by the Navy. Island hoping was how the Marines fought with the Navy to defeat Japan. The Pacific War had as many strategic considerations as the the War in Europe, but the main one had to do with the ships and air craft carriers on both sides. It was a brutal slow process: the Japanese could not believe that the Americans could develop the necessary fighting spirit and discipline possessed by the Japanese. They were wrong on both counts. America fought the war by Island hoping taking back each of the islands the Japanese had conquered during or before WWII.
