In this task, you are given a context, a subject, a relation, and many options. Based on the context, from the options select the object entity that has the given relation with the subject. Answer with text (not indexes).

Q: Context: A chain gun is a type of machine gun or autocannon that uses an external source of power to cycle the weapon rather than diverting energy from the cartridge , and does so via a continuous loop of chain similar to that used on a motorcycle or bicycle . `` Chain gun '' is a registered trademark of Alliant Techsystems Inc. for a chain - powered weapon ., The word bullet is a firearm term. A bullet is a projectile expelled from the barrel of a firearm. The term is from Middle French and originated as the diminutive of the word boulle (boullet) which means "small ball." Bullets are made of a variety of materials. They are available singly as they would be used in muzzle loading and cap and ball firearms, as part of a paper cartridge, and much more commonly as a component of metallic cartridges. Bullets are made in a large numbers of styles and constructions depending on how they will be used. Many bullets have specialized functions, such as hunting, target shooting, training, defense, and warfare. , An autocannon or automatic cannon is a large, fully automatic, rapid-fire projectile weapon that fires armour-piercing or explosive shells, as opposed to the bullet fired by a machine gun. Autocannons often have a larger calibre than a machine gun (e.g., 20 mm or greater), but are usually smaller than a field gun or other artillery. When used on its own, the word "autocannon" indicates a single-barrel weapon. When multiple rotating barrels are involved, the word "rotary" is added, and such a weapon is referred to as a "rotary autocannon." Modern autocannons are typically not single soldier-portable or stand-alone units, rather they are usually vehicle-mounted, aircraft-mounted, or boat-mounted, or even remote-operated as in some naval applications. As such, ammunition is typically fed from a belt to reduce reloading or for a faster rate of fire, but a magazine remains an option. They can use a variety of ammunition: common shells include high-explosive dual-purpose types (HEDP), any variety of armour-piercing (AP) types, such as composite rigid (APCR) or discarding sabot types (APDS)., A battle rifle is a military service rifle that fires a full-power rifle cartridge, such as 7.62×51mm NATO, 7.62×54mmR, 7.92x57mm Mauser, .303 British, or .30-06 Springfield. Compared to assault rifles and their intermediate cartridges, the higher-caliber rounds provide greater power and range, though they have greater weight and produce stronger recoil, making them less than ideal for fully automatic fire., A field gun is an artillery piece. Originally the term referred to smaller guns that could accompany a field army on the march and when in combat could be moved about the battlefield in response to changing circumstances (field artillery), as opposed to guns installed in a fort (garrison artillery/coastal artillery), or to siege cannon or mortars which were too large to be moved quickly, and would be used only in a prolonged siege., A submachine gun (SMG) is an air-cooled, magazine-fed, automatic carbine designed to fire pistol cartridges. The term "submachine gun" was coined by John T. Thompson, the inventor of the Thompson submachine gun., Rate of fire is the frequency at which a specific weapon can fire or launch its projectiles. It is usually measured in rounds per minute (RPM or round/min), or rounds per second (RPS or round/s)., A machine gun is a fully automatic mounted or portable firearm, designed to fire bullets in quick succession from an ammunition belt or magazine, typically at a rate of 300 to 1800 rounds per minute. Fully automatic firearms are generally categorized as submachine guns, assault rifles, battle rifles, automatic shotguns, machine guns, or autocannons. Machine guns with multiple rotating barrels are referred to as "rotary machine guns"., An automatic shotgun is an automatic firearm that fires shotgun shells and uses some of the energy of each shot to automatically cycle the action and load a new round. It will fire repeatedly until the trigger is released or ammunition runs out. Automatic shotguns have a very limited range, but provide tremendous firepower at close range., A shotgun (also known as a scattergun, or historically as a fowling piece) is a firearm that is usually designed to be fired from the shoulder, which uses the energy of a fixed shell to fire a number of small spherical pellets called shot, or a solid projectile called a slug. Shotguns come in a wide variety of sizes, ranging from 5.5 mm (.22 inch) bore up to bore, and in a range of firearm operating mechanisms, including breech loading, single-barreled, double or combination gun, pump-action, bolt-, and lever-action, semi-automatic, and even fully automatic variants., Artillery is a class of large military weapons built to fire munitions far beyond the range and power of infantry's small arms. Early artillery development focused on the ability to breach fortifications, and led to heavy, fairly immobile siege engines. As technology improved, lighter, more mobile field artillery developed for battlefield use. This development continues today; modern self-propelled artillery vehicles are highly mobile weapons of great versatility providing the largest share of an army's total firepower., An assault rifle is a selective-fire rifle that uses an intermediate cartridge and a detachable magazine. Assault rifles were first used during World War II. Though Western nations were slow to accept the assault rifle concept after World War II, by the end of the 20th century they had become the standard weapon in most of the world's armies, replacing semi-automatic rifles, battle rifles and sub-machine guns in most roles. Examples include the StG 44, AK-47 and the M16 rifle., Subject: chain gun, Relation: subclass_of, Options: (A) ability (B) action (C) ammunition (D) army (E) artillery (F) assault rifle (G) autocannon (H) battle (I) battle rifle (J) belt (K) bullet (L) cannon (M) class (N) energy (O) field gun (P) fire (Q) firearm (R) fort (S) gun (T) hunting (U) infantry (V) lighter (W) machine (X) magazine (Y) march (Z) military ([) option (\) part (]) power (^) projectile (_) rate (`) rifle (a) service (b) shooting (c) shot (d) shotgun (e) single (f) solid (g) submachine gun (h) technology (i) term (j) variety (k) vehicle (l) weapon (m) word

A: firearm
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Q: Context: Paul Gage is a research computer scientist who works at Cray Supercomputers . He is most well known for collaborating with David Slowinski on an algorithm that is credited with the discovery of several of the largest Mersenne primes : 2756839  1 in 1992 , 2859433  1 in 1994 , and 21257787  1 in 1996 ., In mathematics, a Mersenne prime is a prime number that is one less than a power of two. That is, it is a prime number that can be written in the form for some integer . They are named after Marin Mersenne, a French Minim friar, who studied them in the early 17th century. The first four Mersenne primes are 3, 7, 31, and 127., A mathematician is someone who uses an extensive knowledge of mathematics in his/her work, typically to solve mathematical problems., David Slowinski is a mathematician involved in prime numbers. His career highlights have included the discovery of several of the largest known Mersenne primes:
He has also written several textbooks on the subject., Subject: paul gage, Relation: occupation, Options: (A) friar (B) mathematician

A: mathematician
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Q: Context: The Berry Islands are a chain of islands and a district of the Bahamas, covering about of the northwestern part of the Out Islands., The Belize Barrier Reef is a series of coral reefs straddling the coast of Belize, roughly offshore in the north and in the south within the country limits. The Belize Barrier Reef is a long section of the Mesoamerican Barrier Reef System, which is continuous from Cancún on the north-eastern tip of the Yucatán Peninsula through the Riviera Maya and up to Honduras, making it the second largest coral reef system in the world after the Great Barrier Reef in Australia. It is Belize's top tourist destination, popular for scuba diving and snorkeling and attracting almost half of its 260,000 visitors. It is also vital to the country's fishing industry., An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island in a river or a lake island may be called an eyot or ait, and a small island off the coast may be called a holm. A grouping of geographically or geologically related islands is called an archipelago, e.g. the Philippines., The Caribbean (or ) is a region that consists of the Caribbean Sea, its islands (some surrounded by the Caribbean Sea and some bordering both the Caribbean Sea and the North Atlantic Ocean) and the surrounding coasts. The region is southeast of the Gulf of Mexico and the North American mainland, east of Central America, and north of South America., The Indian Ocean is the third largest of the world's oceanic divisions, covering (approximately 20% of the water on the Earth's surface). It is bounded by Asia on the north, on the west by Africa, on the east by Australia, and on the south by the Southern Ocean or, depending on definition, by Antarctica. It is named after the country of India. The Indian Ocean is known as "Ratnkara", ""the mine of gems"" in ancient Sanskrit literature, and as "Hind Mahsgar", ""the great Indian sea"", in Hindi., The Great Barrier Reef is the world's largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching for over over an area of approximately . The reef is located in the Coral Sea, off the coast of Queensland, Australia., A cay (or ), also spelled caye or key, is a small, low-elevation, sandy island on the surface of a coral reef. Cays occur in tropical environments throughout the Pacific, Atlantic and Indian Oceans (including in the Caribbean and on the Great Barrier Reef and Belize Barrier Reef)., Little Stirrup Cay , Bahamas , is one of the Berry Islands , a collection of cays and small islands and is located approximately 55 miles north of Nassau . It is used for tourism by Royal Caribbean Cruises Ltd in an exclusive way ., The Out Islands are the islands that make up the Bahamas with the exception of New Providence Island and Grand Bahama Island. There are more than 700 islands in the archipelago that make up The Bahamas, but only 14 of the Out Islands are inhabited. These include the Abacos, Acklins and Crooked Islands, Andros, the Berry Islands, Bimini, Cat Island, Eleuthera, Harbour Island, the Exumas, Inagua, Long Island, Mayaguana, and San Salvador., Subject: little stirrup cay, Relation: country, Options: (A) antarctica (B) atlantic ocean (C) belize (D) hindi (E) honduras (F) philippines (G) the bahamas (H) world

A:
the bahamas
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