The correct answer is: D. All above
The capacity of a lead-acid cell depends on the rate of discharge, temperature, and density of electrolyte.
The rate of discharge is the rate at which the battery is being used. The higher the rate of discharge, the lower the capacity of the battery. This is because the battery has to work harder to provide the same amount of power at a higher rate of discharge.
The temperature of the battery also affects its capacity. The higher the temperature, the higher the capacity of the battery. This is because the chemical reactions in the battery occur faster at higher temperatures.
The density of the electrolyte also affects the capacity of the battery. The higher the density of the electrolyte, the higher the capacity of the battery. This is because the electrolyte is more concentrated at higher densities, and therefore can provide more ions for the chemical reactions in the battery.
In conclusion, the capacity of a lead-acid cell depends on the rate of discharge, temperature, and density of electrolyte.