The group of sentences that most accurately describes the Cuban Missile Crisis is Group A.
Cuban Missile Crisis was a 13-day confrontation (October 16-28, 1962) between the United States and the Soviet Union related to the deployment of Soviet ballistic missiles in Cuba. In addition to being televised worldwide, it was the closest to the beginning of a large-scale nuclear war during the Cold War.
In response to the failed Bay of Pigs invasion of 1961 and the presence of US-based PGM-19 Jupiter ballistic missiles stationed in Italy and Turkey, Soviet leader Nikita Khrushchev decided to agree with Cuba's request to place nuclear missiles on its territory to deter a future US invasion. An agreement was reached during a secret meeting between Khrushchev and Fidel Castro in July and construction of a series of missile launch facilities began after summer.
An election was underway in the United States. The White House denied accusations that it was ignoring Soviet missiles 145 kilometers off the coast of Florida. These missile preparations were confirmed when a US Air Force Lockheed U-2 spy plane produced clear photographic evidence of R-12 Dvina and R-14 Chusovaya ballistic missile installations. The United States established a military blockade to prevent new missiles from entering Cuba, and announced that it would not allow offensive weapons to be delivered to Cuba, demanding that the already delivered weapons be dismantled and returned to the USSR.
After a long period of tense negotiations, an agreement was reached between Kennedy and Khrushchev. Publicly, the Soviets dismantled their weapons in Cuba and took them to the Soviet Union, subject to United Nations verification, in exchange for a US public statement never to invade Cuba without direct provocation. Secretly, the United States also agreed that it would dismantle the entire Jupiter missile network that was deployed in Turkey and Italy against the Soviet Union, but was not known to the public. On November 20, 1962, when all Ilyushin Il-28 offensive missiles and light bombers were removed from Cuba, the blockade was formally ended. Negotiations between the United States and the Soviet Union underscored the need for a quick, clear and direct line. between Washington DC and Moscow. A series of agreements drastically reduced US-Soviet tensions over the following years.