Area where an oceanic plate goes down into the mantle

Subduction zone which is an Area where an oceanic plate goes down into the mantle

An area where an oceanic plates goes down into the mantle is commonly known as a subduction zone. This is where the less dense plate, usually the oceanic, is subducted under the more dense continental crust.

The correct answer is:   [b]:   "physical systems" .

Fresh water that can be used directly by people, animals and plants.