Answer:
Option B
Explanation:
An aqueous solution of sulphuric acid i.e, 38% by weight or having a density of 1.30 g mL-1is used as an electrolyte in lead accumulators,It is consumed during discharging and when the concentration of H2SO4 falls to 1.20 g mL-1 , it requires recharging.Thus, the most suitable option is (b)