As routine maintenance, the bilge manifold valves are periodically removed and examined. Prior to resecuring the valve bonnets, the valve __________.

Correct Answer: Option D — all of the above

Proper maintenance of bilge manifold valves requires a comprehensive inspection. Renewing gaskets ensures pressure integrity, replacing hardened packing prevents stem leakage, and lapping valve seats restores the seal. All these actions are necessary to ensure the reliability of the bilge system, which is critical for vessel safety and pollution prevention.