The correct answer is A) closed. The reasoning is that, except when pumping from a tank, the bilge system valves on a COASTAL DRILLER should be kept closed. This is to prevent water from inadvertently entering the bilge system and potentially causing issues with the vessel's stability and buoyancy. Keeping the bilge valves closed, except when actively pumping, helps maintain the integrity of the vessel's hull and watertight compartments. The other options are incorrect because: B) the "check-stop position" is not a standard setting for bilge valves, C) leaving the valves opened for draining would allow uncontrolled water entry, and D) "cracked open" is also not a recommended setting for bilge valves when not actively pumping.