The highest electrical conductivity of the following aqueous solutions is of

Conductivity of solution depends on the number of ions. Greater the number of ions in the solution , greater will be the conductivity. Stroger the acid , greater its extent of ionization. If we check the given acids acidic strength, 0.1M diflouro acetic acid will have greater ionization as it is stroger due to $-I$ effect. Therefore 0.1M difluoro acetic acid will have greater electrical conductivity.