If one hydraulic pump of an electro-hydraulic steering unit fails, the vessel's steering can initially be maintained by activating which of the following units?

Correct Answer: Option D — standby pump

Electro-hydraulic steering systems utilize redundant power units. Per SOLAS and 46 CFR, dual-pump arrangements allow immediate restoration of hydraulic pressure and steering control by simply starting the standby pump from the bridge or steering gear flat upon primary pump failure.