The correct option is A 2,2
Steps for finding valency factor/n-factor:
1. Find the oxidation state (O.S.) of metal in reactant side.
2. Find the oxidation state of metal in product side.
3. Take the magnitude of difference of two oxidation state |O.S.Product−O.S.Reactant|×number of atom for the valency factor
the reduction reaction is given by Zn+CuSO4→ZnSO4+Cu
O.S. of Zn in reactant side=0
O.S. of Zn in product side
x−2=0
x=+2
valency factor=number of Zn atom×|O.S.Product−O.S.Reactant|
valency factor=1×|+2−0|
valency factor=2
O.S. of Cu in reactant side
x−2=0
x=+2
O.S. of Cu in product side=0
valency factor=number of Cu atom×|O.S.Product−O.S.Reactant|
valency factor=1×|0−2|
valency factor=2