Given the question: Information:  - The Iezerul Mic is a headwater of the Râul Mare in Romania .  - Romania is a sovereign state located in Southeastern Europe. It borders the Black Sea, Bulgaria, Ukraine, Hungary, Serbia, and Moldova. It has an area of and a temperate-continental climate. With 19.94 million inhabitants, the country is the seventh-most-populous member state of the European Union. The capital and largest city, Bucharest, with its 1,883,425 inhabitants is the sixth-largest city in the EU.  - Bulgaria (tr. '), officially the Republic of Bulgaria (tr. '), is a country in southeastern Europe. It is bordered by Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, and the Black Sea to the east. With a territory of , Bulgaria is Europe's 16th-largest country.  - 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.  - The Black Sea is a body of water between Eastern Europe and Western Asia, bounded by Bulgaria, Georgia, Romania, Russia, Turkey, and Ukraine. It is supplied by a number of major rivers, such as the Danube, Dnieper, Rioni, Southern Bug, and Dniester. The Black Sea has an area of (not including the Sea of Azov), a maximum depth of , and a volume of . It is constrained by the Pontic Mountains to the south and by the Caucasus Mountains to the east, and features a wide shelf to the northwest. The longest east-west extent is about .  - Moldova (or sometimes ), or Moldavia, officially the Republic of Moldova, is a landlocked country in Eastern Europe, bordered by Romania to the west and Ukraine to the north, east, and south. The capital city is Chiinu.  - 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.  - Ukraine (tr. ) is a sovereign state in Eastern Europe, bordered by Russia to the east and northeast, Belarus to the northwest, Poland and Slovakia to the west, Hungary, Romania, and Moldova to the southwest, and the Black Sea and Sea of Azov to the south and southeast, respectively. Ukraine is currently in territorial dispute with Russia over the Crimean Peninsula which Russia annexed in 2014 but which Ukraine and most of the international community recognise as Ukrainian. Including Crimea, Ukraine has an area of , making it the largest country entirely within Europe and the 46th largest country in the world. It has a population of about 44.5 million, making it the 32nd most populous country in the world.  - A sovereign state is, in international law, a nonphysical juridical entity that is represented by one centralised government that has sovereignty over a geographic area. International law defines sovereign states as having a permanent population, defined territory, one government, and the capacity to enter into relations with other sovereign states. It is also normally understood that a sovereign state is neither dependent on nor subjected to any other power or state.  - Continental climates are defined in the Köppen climate classification has having a coldest month mean temperature below -3 C (26.6 F) or 0 °C depending on which isotherm used for the coldest month and four months above 10 °C. In the Köppen climate system, Continental climates were bordered to the south by Temperate climates or C climates (coldest month above 0 C, but below 18 C) and to the north by Boreal climate or E climates (only 1 to 3 months with a mean temperature of 50 F). Köppen also defined continental climates as having more than 30 days with continuous snowcover on the ground.   - Bucharest is the capital and largest city of Romania, as well as its cultural, industrial, and financial centre. It is located in the southeast of the country, at , on the banks of the Dâmbovia River, less than north of the Danube River and the Bulgarian border.  - Hungary is a unitary parliamentary republic in Central Europe. It covers an area of , situated in the Carpathian Basin and bordered by Slovakia to the north, Romania to the east, Serbia to the south, Croatia to the southwest, Slovenia to the west, Austria to the northwest, and Ukraine to the northeast. With about 10 million inhabitants, Hungary is a medium-sized member state of the European Union. The official language is Hungarian, which is the most widely spoken Uralic language in the world. Hungary's capital and largest metropolis is Budapest, a significant economic hub, classified as an Alpha- global city. Major urban areas include Debrecen, Szeged, Miskolc, Pécs and Gyr.    After reading the paragraphs above, we are interested in knowing the entity with which 'iezerul mic river' exhibits the relationship of 'instance of'. Find the answer from the choices below.  Choices: - 1  - area  - balkans  - body of water  - border  - capital  - city  - classification  - climate  - country  - economic union  - financial centre  - government  - home  - hungary  - international law  - landlocked country  - law  - market  - member  - metropolis  - month  - official  - part  - peninsula  - republic  - river  - sea  - sovereign state  - state  - temperature  - territorial dispute  - territory  - union  - volume
The answer is:
river