If checking the electrolyte level in a nickel-cadmium (Ni-Cad) battery, then you would use which of the following?

If checking the electrolyte level in a nickel-cadmium (Ni-Cad) battery, then you would use which of the following? 




a. Self leveling syringe.
b. Visual inspection.
c. Hydrometer.
d. Glass tube.



Answer: D