On the DEEP DRILLER, to use the drill water pump to supplement the bilge pumps, it is necessary to open valves 28 and __________.

Correct Answer: Option D — 26

Operating the drill water pump as a backup bilge suction on the DEEP DRILLER requires specific valve line-ups per the vessel's engineering operating manual, designating valve 26 and valve 28 as the primary cross-connection control points.