Please answer the following question: Information: - The Ruhr, or the Ruhr district, Ruhr region, Ruhr area or Ruhr valley, is a polycentric urban area in North Rhine-Westphalia, Germany. With a population density of 2,800/km and a population of eight and a half million, it is the largest urban agglomeration in Germany, and third-largest in the European Union. It consists of several large, industrial cities bordered by the rivers Ruhr to the south, Rhine to the west, and Lippe to the north. In the southwest it borders the Bergisches Land. It is considered part of the larger Rhine-Ruhr metropolitan region of more than 12 million people, which is among the largest in Europe. - Wind is the flow of gases on a large scale. On the surface of the Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the Sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space. Winds are commonly classified by their spatial scale, their speed, the types of forces that cause them, the regions in which they occur, and their effect. The strongest observed winds on a planet in the Solar System occur on Neptune and Saturn. Winds have various aspects, an important one being its velocity; another the density of the gas involved; another its energy content or wind energy. - Dortmund is an independent city in North Rhine-Westphalia, Germany. It is in the middle part of the state and is considered to be the administrative, commercial and cultural centre of the eastern Ruhr area. Its population of 581,612 (2015) makes it the 8th largest city in Germany. Moreover, Dortmund is the largest city by area and population in the Ruhr Area, an urban area with some 5.1 million (2011) inhabitants which is the largest urban agglomeration in Germany. - Latin (Latin: ) is a classical language belonging to the Italic branch of the Indo-European languages. The Latin alphabet is derived from the Etruscan and Greek alphabets. - Westphalia is a region in northwestern Germany and one of the three historic parts of the state of North Rhine-Westphalia. It has an area of 7,802 sq mi (20,208km) and 7.9 million inhabitants. - The Rhine-Ruhr metropolitan region is the largest metropolitan region in Germany with over 11 million inhabitants. It is of polycentric nature and the only megacity in Germany. It covers an area of 7,110 square kilometers and lies entirely within the federal state of North Rhine-Westphalia. The Rhine-Ruhr metropolitan region spreads from Dortmund-Bochum-Essen-Duisburg (Ruhr Area) in the north, to the urban areas of the cities of Monchengladbach, Dusseldorf (the state capital), Wuppertal, Leverkusen, Cologne (the region's largest and Germany's fourth largest city), and Bonn in the south. The location of the Rhine-Ruhr at the heart of the European blue banana makes it well connected to other major European cities and metropolitan areas like the Randstad, the Flemish Diamond and the Frankfurt Rhine Main Region. - Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun and the rotation of the Earth. - Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is filtered through Earth's atmosphere, and is obvious as daylight when the Sun is above the horizon. When the direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat. When it is blocked by clouds or reflects off other objects, it is experienced as diffused light. The World Meteorological Organization uses the term "sunshine duration" to mean the cumulative time during which an area receives direct irradiance from the Sun of at least 120 watts per square meter. Other sources indicate an "Average over the entire earth" of "164 Watts per square meter over a 24 hour day". - The Rhine (, , ) is a European river that begins in the Swiss canton of Graubunden 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 . - Dusseldorf (Low Franconian, Ripuarian: "Dusseldorp" ) is the capital city of the German state of North Rhine-Westphalia and the seventh most populous city in Germany. Dusseldorf 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 Dusseldorf organises nearly one fifth of premier trade shows. - A renewable resource is a natural resource which replenishes to overcome resource depletion caused by usage and consumption, either through biological reproduction or other naturally recurring processes in a finite amount of time in a human time scale. Renewable resources are a part of Earth's natural environment and the largest components of its ecosphere. A positive life cycle assessment is a key indicator of a resource's sustainability. - Electricity generation is the process of generating electric power from other sources of primary energy. For electric utilities, it is the first process in the delivery of electricity to consumers. The other processes, electricity transmission, distribution, and electrical power storage and recovery using pumped-storage methods are normally carried out by the electric power industry. Electricity is most often generated at a power station by electromechanical generators, primarily driven by heat engines fuelled by combustion or nuclear fission but also by other means such as the kinetic energy of flowing water and wind. Other energy sources include solar photovoltaics and geothermal power. - The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, with internal convective motion that generates a magnetic field via a dynamo process.<ref name="doi10.1146/annurev-astro-081913-040012"></ref> It is by far the most important source of energy for life on Earth. Its diameter is about 109 times that of Earth, and its mass is about 330,000 times that of Earth, accounting for about 99.86% of the total mass of the Solar System. About three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron. - RWE AG , until 1990 : Rheinisch - Westfalisches Elektrizitatswerk AG ( Rhine - Westfalia Power Plant ) , is a German electric utilities company based in Essen , North Rhine - Westphalia . Through its various subsidiaries , the energy company supplies electricity and gas to more than 20 million electricity customers and 10 million gas customers , principally in Europe . RWE is the second largest electricity producer in Germany . RWE previously owned American Water , the United States ' largest investor - owned water utility , but this was divested in 2008 . Subsidiary RWE Dea produces some of the oil and gas its parent sells ( annual production is around 2 million m3 of crude oil ( about 365,000 BOE ) and 3 billion m3 of natural gas ( about 18 million BOE , 49,300 BOE a day ) . It is the largest German investor in Egypt ( RWE Dea and RWE Power do business in Egypt ) . Also RWE has begun building more wind farms , a renewable energy business . - In physics, heat is that amount of energy flowing from one body to another spontaneously due to their temperature difference, or by any means other than through work or the transfer of matter. The transfer can be by contact between the source and the destination body, as in conduction; or by radiation between remote bodies; or by conduction and radiation through a thick solid wall; or by way of an intermediate fluid body, as in convective circulation; or by a combination of these. - Essen (Latin: "Assindia") is a city in North Rhine-Westphalia, Germany. Its population of approximately 589,000 makes it the ninth-largest city in Germany. It is the central city of the northern (Ruhr) part of the Rhine-Ruhr metropolitan area and seat to several of the region's authorities. - Electricity is a physical phenomenon associated with the presence of electric charge. Although initially considered a phenomenon separate to magnetism, since the development of Maxwell's Equations both are recognized as part of a single phenomenon:electromagnetism. Various common phenomena are related to electricity, including lightning, static electricity, electric heating, electric discharges and many others. In addition, electricity is at the heart of many modern technologies. - Cologne is the largest city in the German federal State of North Rhine-Westphalia and the fourth-largest city in Germany (after Berlin, Hamburg, and Munich). It is located within the Rhine-Ruhr metropolitan region, one of the major European metropolitan regions and the largest in Germany, with more than ten million inhabitants. - Rain is liquid water in the form of droplets that have condensed from atmospheric water vapor and then precipitatedthat is, become heavy enough to fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. It provides suitable conditions for many types of ecosystems, as well as water for hydroelectric power plants and crop irrigation. - 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 Dusseldorf; the most populous city is Cologne. Four of Germany's ten largest citiesCologne, Dusseldorf, Dortmund, and Essenare located within the state, as well as the largest metropolitan area on the European continent, Rhine-Ruhr. - Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum. The word usually refers to visible light, which is visible to the human eye and is responsible for the sense of sight. Visible light is usually defined as having wavelengths in the range of 400700 nanometres (nm), or 4.00 10 to 7.00 10m, between the infrared (with longer wavelengths) and the ultraviolet (with shorter wavelengths). This wavelength means a frequency range of roughly 430750 terahertz (THz). - A city is a large and permanent human settlement. Although there is no agreement on how a city is distinguished from a town in general English language meanings, many cities have a particular administrative, legal, or historical status based on local law. - Renewable energy is energy that is collected from renewable resources, which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. Renewable energy often provides energy in four important areas: electricity generation, air and water heating/cooling, transportation, and rural (off-grid) energy services. - 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 Dusseldorf. After reading the paragraphs above, we are interested in knowing the entity with which 'rwe' exhibits the relationship of 'part of'. Find the answer from the choices below. Choices: - 16 - 24 - accounting - alps - center - city - consumption - dax - earth - electromagnetic spectrum - europe - european union - eye - gas - german - hour - human - human eye - human settlement - industry - language - latin alphabet - law - liquid - moon - munich - name - organization - outer space - phenomenon - physics - plasma - process - radiation - recovery - rhine - sea - state - state of germany - sun - system - the city - the middle - trade - wall - word - work
A:
dax