Question: Which dog breed is extinct, Japanese Chin or Tahltan Bear Dog?
Context: The Seskar Seal Dog ("Seiskarinhyljekoira") is an extinct dog breed from Finland that was recently recreated.  The modern dogs are not direct descendants of the original breed.  Moreover, they are not used for the same purpose as the original breed.  The original breed is typically called Seskar Seal Dog and the modern version Seskar (or Seiskari) Dog.  Some 200 individuals in Finland represent the modern breed. The Japanese Chin (Japanese: 狆, "chin"), also known as the Japanese Spaniel, is a dog acknowledged for its importance to Japanese nobility.  It is also known for its strabismus of the eyes.  Being both a lap dog and a companion dog, this toy breed has a distinctive heritage. The Karelian Bear Dog (KBD) is a Finnish or Karelian breed of dog.  In its home country, it is regarded as a national treasure.  KBD will hunt a variety of animals.  Its quick reflexes and fearless nature have made it very popular for hunting aggressive game, including bears, moose, and wild boar.  It was the breed's ability to hunt and offer protection against a bear that earned the breed its name. The Airedale Terrier (often shortened to "Airedale"), also called Bingley Terrier and Waterside Terrier, is a dog breed of the terrier type that originated in the valley ("dale") of the River Aire, in the West Riding of Yorkshire, England.  It is traditionally called the "King of Terriers" because it is the largest of the terrier breeds.  The Airedale was bred from the Old English Black and Tan Terrier (now extinct), the Bull Terrier, the Otterhound and probably some other Terrier breeds, originally to serve as an all around working farm dog.  In Britain this breed has also been used as a war dog, guide dog and police dog.  In the United States, this breed has been used to hunt big game, upland birds, and water fowl, and serve in many other working capacities. The Telomian is a breed of dog native to Malaysia.  Though rare, it remains the only known Malaysian dog breed to live outside its homeland.  Malaysian are used to called this dog breed Anjing Kampung which means Village dog in Malay.  This dog breed is still remained rarest in the world. Conformation in dogs refers solely to the externally visible details of a dog's structure and appearance, as defined in detail by each dog breed's written breed standard.  A dog that "conforms" to most of the items of description in its individual breed standard is said to have "good conformation".  Unlike equine conformation, there are no fixed rules for dog conformation, as dogs are the most variable in appearance of any animals ("Phenotypic variation among dog breeds, whether it be in size, shape, or behavior, is greater than for any other animal").  Instead, conformation in dogs is based on the dog type from which the breed developed, along with many details that have been added to the breed standard for purposes of differentiation from other breeds, for working reasons, or for enhancing the beauty of the animals from the viewpoint of the fanciers who wrote the breed standards. Arctocyon ('bear dog') is an extinct genus of ungulate mammals.  "Arctocyon" was a "ground dwelling omnivore", that lived from 61.3-56.8 Ma.  Synonyms of "Arctocyon" include "Claenodon", and "Neoclaenodon".  "Arctocyon" was likely plantigrade, that is, walked like a bear. Twelve states of the United States have designated an official state dog breed.  Maryland was the first state to name a dog breed as a state symbol, naming the Chesapeake Bay Retriever in 1964.  Pennsylvania followed the year after, naming the Great Dane as its official breed.  Dog breeds are mostly affiliated with the states that they originated in.  North Carolina chose the Plott Hound as it was the only dog breed indigenous to the state. A breed standard (also called bench standard or the standard) in the dog fancy is a set of guidelines covering specific "externally observable" qualities such as "appearance", "movement", and "temperament" for that dog breed.  Breed standards are not scientific documents, but are written for each breed by clubs of hobbyists called breed clubs for their own specific requirements.  Details and definitions within breed standards for a specific dog breed may vary from breed club to breed club and from country to country.  Dog breed standards are similar in form and function to breed standards for other domesticated animals. The Tahltan Bear Dog was a breed of dog that was indigenous to Canada.  This breed is believed to be extinct by most authorities.
Answer: Tahltan Bear Dog