Which of the following pairs of elements is most important for the eutrophication process?

Nitrogen and phosphorus are the key nutrients driving eutrophication in water bodies.

Calcium and magnesium affect water hardness, not nutrient-fed algal growth.

Nickel and cobalt are trace metals, not the main eutrophication drivers.

Iron and copper play minor biological roles but do not trigger eutrophication.

Excess nitrogen and phosphorus fuel algal blooms that deplete dissolved oxygen.

Much of this loading comes from fertilizer runoff and untreated sewage.