Context: Germany, officially the Federal Republic of Germany, is a federal parliamentary republic in central-western Europe. It includes 16 constituent states, covers an area of , and has a largely temperate seasonal climate. With about 82 million inhabitants, Germany is the most populous member state of the European Union. After the United States, it is the second most popular immigration destination in the world. Germany's capital and largest metropolis is Berlin. Other major cities include Hamburg, Munich, Cologne, Frankfurt, Stuttgart and Düsseldorf., Duisburg is a German city in the western part of the Ruhr Area ("Ruhrgebiet") in North Rhine-Westphalia. It is an independent metropolitan borough within Regierungsbezirk Düsseldorf. With the world's biggest inland harbor and its proximity to Düsseldorf Airport, Duisburg has become an important venue for commerce and steel production.
In the early Middle Ages it was a royal court of the Franks, first mentioned in writing in 883., The Franks (or ') are historically first known as a group of Germanic tribes that inhabited the land between the Lower and Middle Rhine in the 3rd century AD, and second as the people of Gaul who merged with the Gallo-Roman populations during succeeding centuries, passing on their name to modern-day France and becoming part of the heritage of the modern French people. Some Franks raided Roman territory, while other Frankish tribes joined the Roman troops of Gaul. In later times, Franks became the military rulers of the northern part of Roman Gaul. With the coronation of their ruler Charlemagne as ' by Pope Leo III in 800 AD, he and his successors were recognised as legitimate successors to the emperors of the Western Roman Empire., The 2007 ICF Canoe Sprint World Championships were held in Duisburg, Germany on August 912, 2007 for the record-tying fourth time. The German city had hosted the championships previously in 1979, 1987, and 1995. It tied Duisburg with Belgrade, Serbia (then Yugoslavia) who hosted in 1971, 1975, 1978, and 1982., Düsseldorf (Low Franconian, Ripuarian: "Düsseldörp" ) is the capital city of the German state of North Rhine-Westphalia and the seventh most populous city in Germany. Düsseldorf is an international business and financial centre, renowned for its fashion and trade fairs. The city is headquarters to one Fortune Global 500 and two DAX companies. Messe Düsseldorf organises nearly one fifth of premier trade shows., Düsseldorf Airport (until March 2013 "Düsseldorf International Airport") is the international airport of Düsseldorf, the capital of the German state North Rhine-Westphalia. It is located approximately north of downtown Düsseldorf, and some south-west of Essen in the Rhine-Ruhr area, Germany's largest metropolitan area., 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., Belgrade is the capital and largest city of Serbia. It is located at the confluence of the Sava and Danube rivers, where the Pannonian Plain meets the Balkans. Its name translates to "White city". The urban area of the City of Belgrade has a population of 1.34 million, while over 1.65 million people live within its administrative limits., 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., Gergely Boros is a Hungarian sprint canoer who has competed since the late 2000s . He won a gold medal in the K - 4 200 m event at the 2007 ICF Canoe Sprint World Championships in Duisburg ., North Rhine-Westphalia (, commonly shortened to NRW) is the most populous state of Germany, with a population of approximately 18 million, and the fourth largest by area. Its capital is Düsseldorf; the most populous city is Cologne. Four of Germany's ten largest citiesCologne, Düsseldorf, Dortmund, and Essenare located within the state, as well as the largest metropolitan area on the European continent, Rhine-Ruhr., The Rhine (, , ) is a European river that begins in the Swiss canton of Graubünden in the southeastern Swiss Alps, forms part of the 
Swiss-Austrian, Swiss-Liechtenstein, Swiss-German and then the Franco-German border, then flows through the Rhineland and eventually empties into the North Sea in the Netherlands. 
The largest city on the river Rhine is Cologne, Germany, with a population of more than 1,050,000 people. It is the second-longest river in Central and Western Europe (after the Danube), at about , with an average discharge of about ., Subject: gergely boros, Relation: country_of_citizenship, Options: (A) croats (B) france (C) gaul (D) germany (E) hamburg (F) hungary (G) kingdom of serbia (H) kosovo (I) liechtenstein (J) netherlands (K) romania (L) serbia (M) western roman empire (N) yugoslavia
Output: hungary