Answer: I’m pretty sure it’s B
Convection currents occur in the MANTLE. The mantle is the second layer of the earth after the crust. The mantle is approximately 2900 km thick. Convection currents are triggered or fueled by the heat from the Earth's core.
The part of the mantle closest to the core gets heated. It then becomes less dense than the layers above so it rises. When this rising plume interacts with the crust it cools and becomes more dense than the layers below and so it sinks and this circular motion continues to form convection currents.
Correct answer is filtration.
Wetlands improve water quality by filtration. Wetlands do the process of filtration by trapping the sediments found in water.Wetlands also perform water filtration by nutrient and bacterial absorption. It can be found in all 6 continents (Asia, Africa, North America, South America, Australia, Europe), except Antarctica.
