A

The electrochemical equivalent (ECE) of a material is defined as the mass of the substance that is liberated or deposited at an electrode during electrolysis per unit of electric charge. It depends primarily on the nature of the material, as different materials have differing valencies and conductive properties that affect how much mass will be deposited per unit charge. While the current and amount of charge passed can influence the total mass deposited, the specific electrochemical equivalent is intrinsic to the material itself, making Option A the most accurate choice. Therefore, the correct answer is A.