Ag+(aq) + e- → Ag(s) ; E° = +0.80 V
H+(aq) + e- → 1/2 H2(g) ; E° = 0.00 V
On the basis of their standard reduction potential (E°) values, cathode reaction is given by the one with higher E° values.
Thus Ag+(aq) + e- → Ag(s) reaction will be more feasible at cathode.