Given that
`E_(Ni^(2+)//Ni)^(@)=-0.25V, E_(Cu^(2+)//Cu)^(@)=+0.34V`,
`E_(Ag^(+)//Ag)^(@)=+0.80V , E_(Zn^(2+)//Zn^(-))=-0.76V`.
Which of the following redox processes will not take place in specified direction ?
A. `Ni^(2+)(aq)+Cu(s)rarr Ni(s)+Cu^(2+)(aq)`
B. `Cu(s)+2Ag^(+)(aq)rarr Cu^(2+)(aq)+2Ag(s)`
C. `Cu(s)+2H^(+)(aq)rarr Cu^(2+)(aq)+H_(2)(g)`
D. `Zn(s)+2H^(+)(aq)rarr Zn^(2+)(aq)+H_(2)(g)`
