Final answer:
The deepest parts of the ocean are found in trench zones such as the Challenger Deep, not in submarine canyons. The Challenger Deep reaches approximately 11,000 meters deep, while the abyssal zone is noted for its high pressure and absence of light, starting at depths of 4000 meters.
Step-by-step explanation:
The statement that the deepest portions of the ocean are part of the relatively narrow features called submarine canyons is false. The deepest parts of the ocean are found in areas known as trench zones, such as the Challenger Deep in the Mariana Trench, which is approximately 11,000 meters (about 6.8 miles) deep. The abyssal zone is another deep part of the ocean, at depths of 4000 meters or greater, featuring very high pressure, high oxygen content, low nutrient content, and an absence of plants due to lack of light. In contrast, submarine canyons are indeed deep, steep-sided valleys cut into the seabed of the continental slope, sometimes extending well onto the continental shelf, but they are not synonymous with the deepest parts of the ocean.