[2026] PTE Academic Reading - Multiple Choice, Multiple Answers

The Mariana Trench, located in the western Pacific Ocean, is the deepest oceanic trench on Earth.Its deepest point, known as the Challenger Deep, plunges to an astounding depth of nearly 11,000 meters below sea level.To put this into perspective, if Mount Everest were dropped into the Challenger Deep, its peak would still remain over two kilometers underwater.

This massive crescent-shaped scar in the Earth's crust was formed by a geological process called subduction.It occurs at a convergent plate boundary where the massive Pacific tectonic plate is being continuously forced underneath the smaller Mariana Plate.The conditions at the bottom of the trench are incredibly extreme, characterized by complete darkness, near-freezing temperatures, and crushing hydrostatic pressure that is over a thousand times greater than at the surface.

Despite these seemingly inhospitable conditions, the Mariana Trench is teeming with highly specialized life forms.Because no sunlight can penetrate to these depths, photosynthesis is impossible.Instead, the food web relies heavily on chemosynthesis, where specialized bacteria convert minerals and chemicals expelled from hydrothermal vents into organic matter, sustaining unique creatures like giant amphipods and the ethereal Mariana snailfish.