Title: Kaʻula
Content:  It is located 23 mi west-southwest of Kawaihoa Point on Niihau, and about 150 nmi west of Honolulu. The island is the top of a volcanic tuff cone that rests on top of a larger, submerged shield volcano. At its highest point, the island reaches a height of 548 ft. The ocean has carved large sea cliffs on the sides of the island. There is a large cave on the northwest side of the island called Kahalauaola (Shark Cave). The United States Census Bureau defines Kaula as Census Tract 411 of Kauai County, Hawaii. The 2000 census showed that the uninhabited island had a land area of 158.2 acre. Because of erosion, the island is slowly shrinking. Kaʻula, which he spelled as "Tahoora", was one of the first five islands sighted by Captain James Cook in 1778.
Title: Kailua, Hawaii
Content:  Kailua is located at 21.3975°N, -157.73944°W (21.397370, −157.739515). Nearby towns include Kāneohe, Maunawili, and Waimānalo. According to the United States Census Bureau, the CDP has a total area of 27.4 km2. 20.1 km2 of it is land, and 7.3 km2 of it (26.62%) is water. A significant portion of this water area is Kawainui Marsh, the largest wetland in the Hawaiian Islands and a Ramsar Convention site.
Title: Kailua, Hawaii
Content:  Kailua  is a census-designated place (CDP) in Honolulu County, Hawaii, United States. It lies in the Koolaupoko District of the island of Oahu on the windward coast at Kailua Bay. It is in the judicial district and the ahupua'a named Ko'olaupoko. It is 12 mi northeast of Honolulu – over Nu‘uanu Pali. In the Hawaiian language Kailua means "two seas" or "two currents", a contraction of the words kai (meaning "sea" or "sea water") and elua (meaning "two"); it is so named because of the two former fishponds in the district (Kawainui and Kaelepulu) or the two currents which run through Kailua Bay. Kailua is primarily a residential community, with a centralized commercial district along Kailua Road. The population was 50,000 in 1992. The population was 40,514 at the 2020 census. the population had dropped to 38,000. Places of note in Kailua include Kailua Beach Park, Kaōhao or Lanikai Beach, Kawainui Marsh, Maunawili Falls, and Marine Corps Base Hawaii. It was home to Barack Obama’s winter White House.
Title: Kaʻula
Content:   Kaʻula Island, also called Kaʻula Rock, is a small, crescent-shaped island in the Hawaiian Islands.
Title: Kauai
Content:  Kauai, anglicized as Kauai, is geologically the second-oldest of the main Hawaiian Islands (after Niʻihau). With an area of 562.3 square miles (1,456.4 km2), it is the fourth-largest of these islands and the 21st largest island in the United States. Known also as the "Garden Isle", Kauai lies 73 miles (117 km) across the Kauai Channel, northwest of Oahu. This island is the site of Waimea Canyon State Park and the Na Pali Coast State Park. The United States Census Bureau defines Kauai as census tracts 401 through 409 of Kauai County, Hawaii, which comprises all of the county except for the islands of Kaʻula, Lehua and Niihau. The 2020 United States Census population of the island was 73,298. The most populous town was Kapaa.
Title: Kailua-Kona, Hawaii
Content:  Kailua, a town on the island of Hawaiʻi, is also known by its post office designation Kailua-Kona to differentiate it from Kailua located on the windward side of Oahu island. ("Kona" is the Hawaiian term for "leeward," and all of the Hawaiian Islands have a Kona district, though on some islands the term has fallen out of common use. Kailua-Kona is sometimes erroneously referred to by the name of the district, Kona, in which it is the largest town.) Kailua-Kona is an unincorporated town (Census Designated Place) in Hawaii County, Hawaii, United States, in the North Kona District of the Island of Hawaii. The population was 11,975 at the 2010 census, up from 9,870 at the 2000 census. It is the center of commerce and of the tourist industry on West Hawaii. Kailua-Kona is served by Kona International Airport, located just to the north in the adjacent Kalaoa CDP. Kailua-Kona was the closest major settlement to the epicenter of the 2006 Kiholo Bay earthquake.
Title: Kawelikoa Point
Content:  Kawelikoa Point is a large jutting headland on the south-east coast of the island of Kauai in the Hawaiian Islands.
Title: Kailua, Hawaii
Content:  Kailua has a tropical rainforest climate.
Title: Kailua, Hawaii
Content:  Kailua Beach is crescent-shaped, about 2.5 mi long, and ranging between 50 and 150 ft wide. The ocean bottom fronting the beach slopes gently and beautifully to overhead depths without any coral heads. Light to medium waves support surfing and bodysurfing. The steady trade winds make Kailua Beach a top windsurfing and kitesurfing destination. Robby Naish, first World Champion of windsurfing and Professional Windsurfers Association Hall of Fame inductee, grew up in Kailua. Sea kayaking and stand-up paddleboarding to the protected seabird sanctuaries Flat Island and the Nā Mokulua, popularly known as "the Mokes", have become increasingly popular water activities at the beach.
Title: Kailua High School
Content:  Kailua High School is a four-year public high school located in the Kailua CDP, City and County of Honolulu, Hawaii, United States on the island of O‘ahu. The school serves students grades 9 through 12. As of the 2000 U.S. Census the U.S. Census Bureau defined the school as being in the Maunawili CDP, but as of the 2010 U.S. Census it was redefined as being in Kailua CDP.

Question: which island is kailua on?
Answer: Hawaii.