Please answer the following question: Information: - 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 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 Cancun on the north-eastern tip of the Yucatan 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. - The Abaco Islands lie in the northern Bahamas 180 miles (290km) east of south Florida with similar weather with the exception of local patterns. They comprise the main islands of Great Abaco and Little Abaco, along with smaller barrier cays. The northernmost are Walker's Cay, and its sister island Grand Cay. To the south, the next inhabited islands are Spanish Cay and Green Turtle Cay, with its settlement of New Plymouth, Great Guana Cay, private Scotland Cay, Man-O-War Cay, and Elbow Cay, with its settlement of Hope Town. Southernmost are Tilloo Cay and Lubbers Quarters. Another of note off Abaco's western shore is onetime Gorda Cay, now a Disney Island and cruise ship stop and renamed Castaway Cay. Also in the vicinity is Moore's Island. On the Big Island of Abaco is Marsh Harbour, the Abacos' commercial hub and the Bahamas' third largest city, plus the resort area of Treasure Cay. Both have airports. A few mainland settlements of significance are Coopers Town and Fox Town in the north and Cherokee and Sandy Point in the south. Administratively, the Abaco Islands constitute seven of the 31 Local Government Districts of the Bahamas: Grand Cay, North Abaco, Green Turtle Cay, Central Abaco, South Abaco, Moore's Island, and Hope Town. - 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. - Coral reefs are diverse underwater ecosystems held together by calcium carbonate structures secreted by corals. Coral reefs are built by colonies of tiny animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups. The polyps belong to a group of animals known as Cnidaria, which also includes sea anemones and jellyfish. Unlike sea anemones, corals secrete hard carbonate exoskeletons which support and protect the coral polyps. Most reefs grow best in warm, shallow, clear, sunny and agitated waters. - 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. - Hope Town is one of the districts of the Bahamas, on the Abaco islands as well as a small village on Elbow Cay, located in Abaco. The area had a population of 458 in 2010. - Elbow Cay is a cay in the Abaco Islands of the Bahamas. Originally populated by British loyalists fleeing the newly independent United States of America in 1785, it has survived on fishing, boat building, and salvage. Its main village of Hope Town surrounds a protected harbor with a noted red-and-white-striped lighthouse built in 1863. - 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). - Anna Cay is a small cay in the Abaco chain of the Bahamas . It resides at the entrance to the North End public dock on Elbow Cay near Hopetown . The cay is home to one residence which is colored pink . - Corals are marine invertebrates in the class Anthozoa of phylum Cnidaria. They typically live in compact colonies of many identical individual polyps. The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton. - Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. It is defined by size, being finer than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e. a soil containing more than 85% sand-sized particles by mass. After reading the paragraphs above, we are interested in knowing the entity with which 'anna cay' exhibits the relationship of 'instance of'. Find the answer from the choices below. Choices: - area - boat - building - cay - class - cluster - country - definition - diving - fox - government - gulf - hindi - india - island - key - material - mineral - ocean - peninsula - point - population - reef - region - sea - series - size - skeleton - soil type - surface - system - tourist destination - town - treasure - war - weather
Answer:
island