Which island is not part of the United States Virgin Islands?

The United States Virgin Islands (abbreviated USVI; also called the U.S. Virgin Islands or American Virgin Islands), officially the Virgin Islands of the United States, are a group of Caribbean islands and an unincorporated and organized territory of the United States.The islands are geographically part of the Virgin Islands archipelago and are located in the Leeward Islands of the Lesser Antilles to the east of Puerto Rico and west of the British Virgin Islands.

The U.S. Virgin Islands consists of the main islands of Saint Croix, Saint John, and Saint Thomas, and many other surrounding minor islands.The total land area of the territory is 133.73 square miles (346.36 km2).The territory's capital is Charlotte Amalie on the island of St. Thomas.

Previously known as the Danish West Indies of the Kingdom of Denmark–Norway (from 1754 to 1814) and the independent Kingdom of Denmark (from 1814 to 1917), they were sold to the United States by Denmark in the 1917 Treaty of the Danish West Indies.They are classified by the United Nations as a Non-Self-Governing Territory, and are currently an organized, unincorporated United States territory.

Saint Kitts, also known more formally as Saint Christopher Island, is an island in the West Indies. The west side of the island borders the Caribbean Sea, and the eastern coast faces the Atlantic Ocean. Saint Kitts and the neighbouring island of Nevis constitute one country: the Federation of Saint Kitts and Nevis.