(a, b) Conductivity of electrolyte solution is due to presence of mobile ions in the solution. This type of conductance is known as ionic conductance. Conductivity of these type of solutions depend upon
(i) the nature of electrolyte added
(ii) size of the ion produced and their solvation
(iii) concentration of electrolyte
(iv) nature of solvent and its viscosity
While power of source or distance between electrodes has no effect on conductivity of electrolyte solution.
Hence, options (a) and (b) are the correct choices.