Explanation:

Both statements are correct.

• Statement 1 is incorrect: Agalega islands have volcanic past however it was not created due to subsidence of caldera of an extinct volcano.

• Statement 2 is incorrect: There is no such lease agreement between India and Mauritius over Agalega islands.

Agaléga (French: îles Agaléga) is a dependency of Mauritius which consists of two outer islands located in the Indian Ocean, about 1,050 km (650 mi) north of Mauritius Island.

• Prime Minister Narendra Modi and Mauritian Prime Minister Pravind Jugnauth jointly inaugurated the new airstrip of Agaléga Islands in Mauritius.

• The climate is hot and humid and the average annual temperature is 26 °C (79 °F), ranging from a minimum of 22.5 °C (72.5 °F) and a maximum of 30.6 °C (87.1 °F).

• April is the hottest month of the year. The tropical climate is conducive to the development of mangrove and coconut trees that cover the two islets.

• A 2015 memorandum of understanding on India–Mauritius military cooperation envisaged developing the Agaléga islands for an Indian military base.

Why in News?

• Prime Minister Narendra Modi and Mauritian Prime Minister Pravind Jugnauth jointly inaugurated the new airstrip of Agaléga Islands in Mauritius.

Hence option 4th is correct.