The correct answer is: The Soviets backed down and pledged to remove the missiles in return for a U.S. pledge not to invade Cuba.
The Cuban Missile Crisis reached a resolution when Soviet Premier Nikita Khrushchev agreed to dismantle the missile installations in Cuba in exchange for a U.S. commitment not to invade Cuba. Additionally, there were secret negotiations that included the future removal of U.S. missiles from Turkey.