Answer:
Option A, North Atlantic Treaty Organization (NATO), is the right answer.
Explanation:
NATO is the abbreviation of the North Atlantic Treaty Organization. Establish on 4th April 1949 by the North Atlantic Treaty, NATO is a military alliance. This organization tried to create a counterweight to the army of the Soviet Union stationed Eastern and Central Europe following the Second World War. NATO is an organization which forms a policy of collective resistance whereby its member states conform to mutual support in acknowledgement to an attack from outside.
