Which statement is true about so4 2− ?

it is a polyatomic cation because it has more than one atom and a positive charge.

it is a polyatomic cation because it has more than one atom and a negative charge.

it is a polyatomic anion because it has more than one atom and a negative charge.

it is a polyatomic anion because it has more than one atom and a positive charge.

The answer to your question is: the third option

Explanation:

                                           SO₄  ⁻²

Polyatomic ion is a molecule composed by 2 or more atoms, so SO₄⁻² is a polyatomic ion.

Cation: is an ion that has a positive charge.

Anion: is an ion that has a negative charge.

so    SO₄ ⁻²   is a polyatomic anion because it is composed by two elements  and has a negative charge.

It is a polyatomic anion because it has more than one atom and a negative charge.