The correct answer is: "the capture of Berlin"
The capture of Berlin was the final major offensive of WWII. It took place in April 1945 and it was headed by the Soviet Union. The fall of Berlin, the capital of the Nazi Germany, was the last barrier in the European theatre to achieve the end and the absolute defeat of the Third Reich.
Moreover, during this attack Hitler killed himself in a bunker as he could not stand to see the city captured and his power lost.
