Context: The United Nations (UN) is an intergovernmental organization to promote international co-operation. A replacement for the ineffective League of Nations, the organization was established on 24 October 1945 after World War II in order to prevent another such conflict. At its founding, the UN had 51 member states; there are now 193. The headquarters of the United Nations is in Manhattan, New York City, and experiences extraterritoriality. Further main offices are situated in Geneva, Nairobi, and Vienna. The organization is financed by assessed and voluntary contributions from its member states. Its objectives include maintaining international peace and security, promoting human rights, fostering social and economic development, protecting the environment, and providing humanitarian aid in cases of famine, natural disaster, and armed conflict., The North Atlantic Treaty Organization (NATO  '), also called the North Atlantic Alliance, is an intergovernmental military alliance based on the North Atlantic Treaty which was signed on 4 April 1949. The organization constitutes a system of collective defence whereby its member states agree to mutual defence in response to an attack by any external party. Three NATO members are permanent members of the United Nations Security Council with the power to veto and are officially nuclear-weapon states: the United States, France and the United Kingdom. NATO's headquarters are located in Haren, Brussels, Belgium, where the Supreme Allied Commander also resides. Belgium is one of the 28 member states across North America and Europe, the newest of which, Albania and Croatia, joined in April 2009. An additional 22 countries participate in NATO's Partnership for Peace program, with 15 other countries involved in institutionalized dialogue programmes. The combined military spending of all NATO members constitutes over 70% of the global total. Members' defence spending is supposed to amount to 2% of GDP., Metohija or Dukagjini) is a large basin and the name of the region covering the southwestern part of Kosovo. The region covers 35% (3,891 km) of Kosovo's total area. According to the 2011 census, the population of the region is 700,577., Albania (; ), officially the Republic of Albania, is a sovereign state in Southeastern Europe. It has a population of 3.03 million as of 2016. Tirana is the nation's capital and largest city, followed by Durrës and Vlorë. Albania is located in the south-western part of the Balkan peninsula, bordered by Montenegro to the northwest, Kosovo to the northeast, the Republic of Macedonia to the east, and Greece to the south and southeast. The country has a coastline on the northern shore of the Mediterranean Sea, the Adriatic Sea to the west and the Ionian Sea to the southwest where the Albanian Riviera begins. Albania is less than from Italy, across the Strait of Otranto which connects the Adriatic Sea to the Ionian Sea., The European Union (EU) is a political and economic union of member states that are located primarily in Europe. It has an area of , and an estimated population of over 510 million. The EU has developed an internal single market through a standardised system of laws that apply in all member states. EU policies aim to ensure the free movement of people, goods, services, and capital within the internal market, enact legislation in justice and home affairs, and maintain common policies on trade, agriculture, fisheries, and regional development. Within the Schengen Area, passport controls have been abolished. A monetary union was established in 1999 and came into full force in 2002, and is composed of 19 EU member states which use the euro currency., Pristina, also spelled Prishtina or Priština, is the capital and largest city of Kosovo. It is the administrative center of the homonymous municipality and district., Kosovo and Metohija, officially the Autonomous Province of Kosovo and Metohija, known as short Kosovo or simply Kosmet, refers to the region of Kosovo as defined in the Constitution of Serbia. The territory of the province is disputed between Serbia and the self-proclaimed Republic of Kosovo, who has "de-facto" control., Piribeg ( Albanian : Piribeg ; Macedonian :  ) is a mountain located between Kosovo and the Republic of Macedonia . Piribeg reaches a height of 2,524m above sea level and is a peak of the eastern part of the Šar Mountains . Located on the slopes of Piribeg is the largest ski centre in Kosovo , Brezovica . At the peak of Piribeg , there is a large pole that brings people by elevator to the top of the peak at 2,524m . From there they are free to ski down as far as the ski centre ., Kosovo  is a disputed territory and partially recognised state in Southeast Europe that declared independence from Serbia in February 2008 as the Republic of Kosovo. Kosovo is landlocked in the central Balkan Peninsula. Its capital and largest city is Pristina. It is bordered by the Republic of Macedonia and Albania to the south, Montenegro to the west, and the uncontested territory of Serbia to the north and east. While Serbia recognises administration of the territory by Kosovo's elected government, it still continues to claim it as its own Autonomous Province of Kosovo and Metohija., Macedonia ( tr. "Makedonija"), officially the Republic of Macedonia (Macedonian: , tr. "Republika Makedonija"), is a country in the Balkan peninsula in Southeast Europe. It is one of the successor states of the former Yugoslavia, from which it declared independence in 1991. It became a member of the United Nations in 1993, but, as a result of an ongoing dispute with Greece over the use of the name "Macedonia", was admitted under the provisional description the former Yugoslav Republic of Macedonia (sometimes unofficially abbreviated as FYROM and FYR Macedonia), a term that is also used by international organizations such as the European Union, the Council of Europe and NATO., Montenegro (or or ; Montenegrin: "Crna Gora" /   , meaning "Black Mountain") is a sovereign state in Southeastern Europe. It has a coast on the Adriatic Sea to the south-west and is bordered by Croatia to the west, Bosnia and Herzegovina to the northwest, Serbia to the northeast, Kosovo to the east, and Albania to the south-east. Its capital and largest city is Podgorica, while Cetinje is designated as the Old Royal Capital ("prijestonica")., Greece (' ), officially the Hellenic Republic (Greek: ' ), historically also known as Hellas ("" ), is a country in southeastern Europe. 
Greece's population is approximately 10.955 million as of 2015. Athens is the nation's capital and largest city, followed by Thessaloniki., Yugoslavia (/, ) was a country in Southeast Europe during most of the 20th century. It came into existence after World War I in 1918 under the name of the Kingdom of Serbs, Croats and Slovenes by the merger of the provisional State of Slovenes, Croats and Serbs (itself formed from territories of the former Austro-Hungarian Empire) with the formerly independent Kingdom of Serbia. The Serbian royal House of Karaorevi became the Yugoslav royal dynasty. Yugoslavia gained international recognition on 13 July 1922 at the Conference of Ambassadors in Paris. The country was named after the South Slavic peoples and constituted their first union, following centuries in which the territories had been part of the Ottoman Empire and Austria-Hungary., The Šar Mountains (Macedonian and ) or Sharr Mountains, form a mountain range in the Balkans that extends from Kosovo and the northwest of the Republic of Macedonia, to northeastern Albania., Serbia, officially the Republic of Serbia, is a sovereign state situated at the crossroads of Central and Southeast Europe, covering the southern part of the Pannonian Plain and the central Balkans. Relative to its small territory, it is a diverse country distinguished by a "transitional" character, situated along cultural, geographic, climatic and other boundaries. Serbia is landlocked and borders Hungary to the north; Romania and Bulgaria to the east; Macedonia to the south; and Croatia, Bosnia-Herzegovina, and Montenegro to the southwest; it also claims a border with Albania through the disputed territory of Kosovo. Serbia numbers around 7 million residents, and its capital, Belgrade, ranks among the largest cities in Southeast Europe., Southeast Europe or Southeastern Europe is a geographical region of Europe, consisting primarily of the Balkan peninsula. Sovereign states that are, at least partially, included in the region are, in alphabetical order, Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Greece, Kosovo, Macedonia, Moldova, Montenegro, Romania, Serbia, Slovenia and Turkey., Europe is a continent that comprises the westernmost part of Eurasia. Europe is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, and the Mediterranean Sea to the south. To the east and southeast, Europe is generally considered as separated from Asia by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways of the Turkish Straits. Yet the non-oceanic borders of Europea concept dating back to classical antiquityare arbitrary. The primarily physiographic term "continent" as applied to Europe also incorporates cultural and political elements whose discontinuities are not always reflected by the continent's current overland boundaries., The Balkan Peninsula, or the Balkans, is a peninsula and a cultural area in Eastern and Southeastern Europe with various and disputed borders. The region takes its name from the Balkan Mountains that stretch from the Serbia-Bulgaria border to the Black Sea., Subject: piribeg, Relation: country, Options: (A) albania (B) atlantic ocean (C) belgium (D) croatia (E) european union (F) greece (G) hungary (H) kingdom of serbia (I) kosovo (J) macedonia (K) moldova (L) montenegro (M) ottoman empire (N) serbia (O) united kingdom (P) united states (Q) world (R) yugoslavia
Output: serbia