Which of the Following Reactions Is an Oxidation-Reduction Reaction

Multiple Choice

Which of the following reactions is an oxidation-reduction reaction?

A) NH₄HS(s) → NH₃(g) + H₂S(g)
B) 2 NaHCO₃(s) → Na₂CO₃(s) + H₂O(g) + CO₂(g)
C) N₂O₄(g) → 2 NO₂(g)
D) 2 SO₂(g) + O₂(g) → 2 SO₃(g)
E) 2 CH₃COOH(aq) + Ba(OH) ₂(aq) → Ba(CH₃COO) ₂(aq) + 2 H₂O(l)