What is the name of the intergovernmental military alliance between 30 European and North American countries?

The correct answer is D, The North Atlantic Treaty Organization. NATO is the military alliance of European and North American states, formed by the North Atlantic Treaty signed at Washington on 4 April 1949 by twelve founding members, and its membership has grown in rounds since then. Its headquarters is at Brussels in Belgium, and Article 5 of the treaty is its core promise: an armed attack on one member is treated as an attack on all. Note that the paper's figure of 30 members belongs to the year the question was set, as the alliance has admitted more states since. Options A, B and C name no real body; they are invented labels built from military-sounding words, and none of them appears in any list of international organisations. A useful contrast is the Warsaw Pact of 1955, the Soviet-led bloc that stood against NATO until it dissolved in 1991. Exam tip: NATO — treaty signed 4 April 1949 at Washington, headquarters Brussels, Article 5 for collective defence.