The standard potentials at 298 K for the following half reactions are as given Zn2++2e-⇄Zn           Eo=−0.762 V2H++2e-→H2(g)         Eo=0.000 VCr3++3e-⇄Cr           Eo=−0.740 VFe3++2e-→Fe2+       Eo=0.772 VWhich of the following is the strongest reducing agent?