Explanation:

It is an island of the British Indian Ocean Territory, an overseas territory of the United Kingdom.

• It is the largest of 60 small islands comprising the Chagos Archipelago.
• The Portuguese were the first Europeans to find it and it was then settled by the French in the 1790s and transferred to British rule after the Napoleonic Wars.
• In 1965, Britain separated the Chagos Islands from Mauritius and set up a joint military base with the United States on Diego Garcia.
• Britain insists the islands belong to London and has renewed a lease agreement with the United States to use Diego Garcia until 2036.

Hence only statement 1st is correct.