Which Is True When Electrochemical Cells Are Used as Chemical

Which is true when electrochemical cells are used as chemical probes?
I.All concentrations in the half-cells must be known except for the analyte of interest.
II. The analyte concentration is calculated from the equilibrium cell potential.
III. Equilibrium between the half-cells is established.
IV. Equilibrium within each half-cell is established and is assumed to remain at equilibrium.
V. Half-cells other than the S.H.E.can be used to determine pH.

A) II,III,and IV
B) I,IV,and V
C) I and II
D) III,IV,and V
E) I,II,and V