To charge a bladder type hydraulic accumulator __________.

Correct Answer: Option C — remove all hydraulic system pressure and bring the pneumatic pressure to the accumulator preload pressure

Precharging an accumulator requires the hydraulic side to be completely depressurized to ensure the bladder is fully expanded against the gas side. The nitrogen is then charged to the manufacturer's specified preload pressure, which is typically a percentage of the minimum system operating pressure.