Correct answer: A. Allied landing in Normandy
Explanation: The direct answer is A: the Allied landing in Normandy. D-Day usually refers to 6 June 1944, when Allied forces began the large amphibious invasion of German-occupied Normandy in northern France during the Second World War. This operation opened a major Western Front and helped the Allies move toward the liberation of France and western Europe. Option A is correct because it names the Normandy landings. Option B, the attack on Pearl Harbor, occurred on 7 December 1941 and was a Japanese attack on a US naval base in Hawaii; it was not D-Day. Option C, the bombing of Hiroshima, happened in August 1945 and was an atomic bombing near the end of the war, not the Normandy invasion. Option D, construction of the Berlin Wall, began in 1961 during the Cold War, long after the Second World War. Do not confuse the date or event: D-Day means the Allied landing, not every major World War II event. Memory cue: D-Day = 6 June 1944 = Normandy landings.