# The standard reduction potentials for $Zn^{2+}/Zn, Ni^{2+}/Ni$ and $Fe^{2+}/Fe$ are -0.76, -0.23 and -0.44V respectively. The reaction $X + Y^2 \to X^{2+} + Y$ will be spontaneous when :
( A ) $X = Ni, Y = Fe$
( B ) $X = Fe, Y = Zn$
( C ) $X = Zn, Y= Ni$
( D ) $X = Ni, Y = Zn$