Solution:
World War II was fought between the Axis powers and the Allied powers. The Axis powers comprised Germany, Italy and Japan. The Allied powers comprised Britain and France initially. However, later on, the US joined the allied powers. Initially, the US didn’t join the war to avoid the losses it had faced after the first world war. However, while Japan was expanding towards the east, it bombed Pearl Harbour, the US naval base. This incident enraged the USA, and it entered the war. The entry of the USA paved the way for the defeat of the axis powers. The USA concluded the Second World war by bombing Hiroshima in Japan.Thus, both the Assertion and Reason are true, and the Reason is the correct explanation of the Assertion.
