Task: Question Answering
Input (English): Context: A nebula (Latin for "cloud"; pl. nebulae, nebulæ, or nebulas) is an interstellar cloud of dust, hydrogen, helium and other ionized gases. Originally, "nebula" was a name for any diffuse astronomical object, including galaxies beyond the Milky Way. The Andromeda Galaxy, for instance, was once referred to as the "Andromeda Nebula" (and spiral galaxies in general as "spiral nebulae") before the true nature of galaxies was confirmed in the early 20th century by Vesto Slipher, Edwin Hubble and others., In astronomy and physical cosmology, the metallicity or Z is the fraction of mass of a star or other kind of astronomical object that is not in hydrogen (X) or helium (Y). Most of the physical matter in the universe is in the form of hydrogen and helium, so astronomers use the word "metals" as a convenient short term for "all elements except hydrogen and helium". This usage is distinct from the usual physical definition of a solid metal. The rationale for the astronomical usage is that in the high-temperature and pressure environment of a star, atoms do not undergo chemical reactions and effectively have no chemical properties, including that of being a metal as usually understood. For example, stars and nebulae with relatively high abundances of carbon, nitrogen, oxygen, and neon are called "metal-rich" in astrophysical terms, even though those elements are non-metals in chemistry., AB Doradus Moving Group is a group of about 30 associated stars that are moving through space together with the star AB Doradus . A moving group is distinguished by its members having about the same age , composition ( or metallicity ) and motion through space . Hence they most likely formed in the same location . This group is located about 20 parsecs from the Earth and is the closest known co-moving group . The average space velocity of this group has components of U =  8 , V =  27 and W =  14 km / s. About 10 of these stars form a nuclear group within a volume roughly 10 parsecs across . The proximity of this moving group makes it useful for studies of shared stellar properties , as well as detection of companions through direct imaging . These can be used for refinement of young stellar models , for example ., AB Doradus is a pre-main-sequence quadruple star system in the constellation Dorado. The primary is a flare star that shows periodic increases in activity., Dorado (English pronunciation: ) is a constellation in the southern sky. It was named in the late 16th century and is now one of the 88 modern constellations. Its name refers to the dolphinfish ("Coryphaena hippurus"), which is known as "dorado" in Portuguese, although it has also been depicted as a swordfish. Dorado contains most of the Large Magellanic Cloud, the remainder being in the constellation Mensa. The South Ecliptic pole also lies within this constellation., Subject: ab doradus moving group, Relation: constellation, Options: (A) andromeda (B) dorado
Output (English): dorado