For a Spontaneous Electrochemical Reaction to Occur, What Criteria Need

For a spontaneous electrochemical reaction to occur, what criteria need to be met?

A) The half-cell reduction potentials must both be large.
B) The reduction potential and the oxidation potential have to have opposite signs.
C) The sum of the reduction potential and the oxidation potential should be positive.
D) The sum of the reduction potentials must be greater than zero.
E) The number of electrons in the half cell reactions must be the same.