Technician A says that distilled or clean drinking water should be added to a battery when the electrolyte level is low. Technician B says that fresh electrolyte (solution of acid water) should be added. Which technician is correct?
A. Technician A is correctB. Technician B is correctC. Both technician A and BD. Neither A nor B

Both Technician A and Technician B is correct. because the basic fundamental behind the storage of energy in the batteries is its electrolytic ions which create the potential difference we get on its terminals.

Explanation:

When the electrolyte level is low we put distilled water in a battery to maintain the electrolyte level and not the fresh electrolyte( solution of water and acid)  itself. The water present in the electrolyte is converted to hydrogen and oxygen gases. As we know clean drinking water is poor in dissolved salts and ions which will not be able to hold the required electric potential in the electrolyte of the battery.Whereas a solution of acid and water is added to the battery as its electrolyte which has a good quantity of hydronium cations and the corresponding compound's anion serving as a medium to store the potential difference.