When troubleshooting a lead-acid storage battery, what is the best method for detecting a weak or dead cell?

Correct Answer: Option B — comparing the specific gravity of the electrolyte in each cell

The specific gravity of the electrolyte is directly proportional to the state of charge in a lead-acid cell. By comparing the hydrometer readings of each cell, a technician can identify a weak or dead cell that fails to reach the same density as the others, indicating internal degradation.