The correct answer is option 1: Indian Ocean. The Sunda Trench is located in the Indian Ocean. It is a deep-water trench that stretches along the western side of Sumatra and Java, two large islands in Indonesia. The trench is part of the larger Ring of Fire, which is an area in the basin of the Pacific Ocean where many earthquakes and volcanic eruptions occur. The Sunda Trench is formed by the subduction of the Australian Plate beneath the Sunda Plate, and it reaches depths of up to 7,725 meters (25,344 feet) at certain points. The Indian Ocean is the third-largest ocean in the world, covering approximately 20% of the Earth`s water surface.