Which of the following world war ii events occurred in 1945?

January 12, 1945
The Soviets launch a new offensive, liberating Warsaw and Krakow in January, capturing Budapest after a two-month siege on February 13, driving the Germans and their Hungarian collaborators out of Hungary in early April, forcing the surrender of Slovakia with the capture of Bratislava on April 4, and capturing Vienna on April 13.

March 7, 1945
US troops cross the Rhine River at Remagen.

April 16, 1945
The Soviets launch their final offensive, encircling Berlin.

April 1945
Partisan units, led by Yugoslav Communist leader Josip Tito, capture Zagreb and topple the Ustasa regime. The top Ustasa leaders flee to Italy and Austria.

April 30, 1945
Hitler commits suicide.

May 7, 1945
Germany surrenders to the western Allies.

May 9, 1945
Germany surrenders to the Soviets.

May 1945
Allied troops conquer Okinawa, the last island stop before the Japanese islands.

August 6, 1945
The United States drops an atomic bomb on Hiroshima.

August 8, 1945
The Soviet Union declares war on Japan and invades Manchuria.

August 9, 1945
The United States drops an atomic bomb on Nagasaki.

September 2, 1945
Having agreed in principle to unconditional surrender on August 14, 1945, Japan formally surrenders, ending World War II.

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a is correct

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