Ag/AgCl(s)/KCl electrode is :-
(1) Reversible w.r.t cation
(2) Reversible w.r.t Cl– ion
(3) Reversible w.r.t K+ ion
(4) Reversible w.r.t Ag+ ion
Kindly explain.

Dear Student,

The electrode Ag/AgCl is dipped in KCl solution. A thin layer of AgCl is coated on Ag electrode.
The reaction happening is 
Ag(s)  + Cl-(aq) ----> AgCl(s) + e-
AgCl is used in the reaction but due to presence of Cl- ion, the AgCl is being formed again. So, the reaction is reversible with respect to Cl- ion. 
The correct option is (2).

Regards