What is the name of the trench that contains the Challenger Deep?

The trench that contains the Challenger Deep is the Mariana Trench.

Located in the western Pacific Ocean, the Mariana Trench is a crescent-shaped depression east of the Mariana Islands. Its deepest section, the Challenger Deep, reaches roughly 11,000 meters below sea level, making it the deepest known point on Earth's seabed.

The name Challenger Deep comes from the British survey ships HMS Challenger and HMS Challenger II, whose expeditions identified and measured the extreme depth. The trench formed where the Pacific Plate is forced beneath the smaller Mariana Plate, a process called subduction.

A common mix-up is to answer Challenger Deep itself. That is the deepest basin within the Mariana Trench, not the name of the larger trench. The trench is also sometimes confused with the Tonga Trench, which is the second deepest ocean trench and lies in the southwestern Pacific.