Consider the following standard reduction potentials: O₂ (g) + 4 H⁺ (aq) + 4e− → 2 H₂O (l) +1.23 V Ni²⁺ (aq) + 2 e− → Ni (s) −0.28 V Fe²⁺ (aq) + 2 e− → Fe (s) −0.45 V Zn²⁺ (aq) + 2 e− → Zn (s) −0.77 V Which process will occur to act as a sacrificial anode for iron? a. 2 H₂O (l) to O₂ (g) b. Ni²⁺ (aq) to Ni (s) c. Zn²⁺ (aq) to Zn (s) d. Ni (s) to Ni²⁺ (aq) e. Zn (s) to Zn²⁺ (aq) f. O₂ (g) to 2 H₂O (l)