The Cheronobyl disaster or known as the Cheronobyl accident was a disastrous nuclear accident happened on April 26, 1986 in the Chernobyl Nuclear Power Plant near Pripyat in Northern Ukraine in what was then included in the Ukraine Soviet Socialist Republic of the Sovient Union (USSR).
They thought it would be over by Christmas
The Korean War was the second war in which the United Nations played a military role. The correct option among all the options given in the question is the second option. It was the toughest test for the United Nations after its inception. It was clear that the United Nations forces sent to Korea was dominated by American soldiers, but several other countries did participate in it.