In order to prevent the unnecessary release of hydrocarbons to atmosphere, when taking on departure ballast, one method used is to _________.

Correct Answer: Option A — allow entering ballast to displace the inert gas to a tank where cargo is currently being discharged

MARPOL Annex VI and inert gas system protocols require that displaced hydrocarbon vapors be managed to prevent atmospheric pollution. Routing displaced inert gas to a cargo tank during ballasting operations effectively contains the vapors within the closed system, preventing their release through the pressure/vacuum relief valves or mast risers.