<span>the answer is Mesopotamians</span>
The correct answer is "A".
The Domino Theory was developed in 1950 in the US administration. It proposed the idea that if one country in a region was governed by a left-wing power which shared communist beliefs, neighbor countries will follow suit. This led the United States to get involved in numerous armed conflicts around the world, such as the Korean War, in order to prevent the spread of Communism.
The US did complain, a lot. Mostly due to that fact that Western Berlin which was controlled By the USA, France and Britian was securely behind this barrier and so to supply half of an entire city they had to fly in 24/7 airlift cargo missions for weeks on end to keep the city from starving.
