29. Which of the following is the strongest reducing agent? \( \text{Zn}^{2+} + 2\text{e}^- \rightleftharpoons \text{Zn} \quad E^\circ = -0.76 \text{ V}; \text{MnO}_4^- + 4\text{H}^+ + 3\text{e}^- \rightleftharpoons \text{MnO}_2 + 2\text{H}_2\text{O} \quad E^\circ = 1.68 \text{ V}; 2\text{H}^+ + 2\text{e}^- \rightleftharpoons \text{H}_2 \quad E^\circ = \) 0.00 V; \( \text{Cl}_2 + 2\text{e}^- \rightleftharpoons 2\text{Cl}^- \quad E^\circ = 1.36 \text{ V}. \)
(A) Zn
(B) MnO₂
(C) H₂
(D) Cl₂