Which space(s) is(are) NOT exempt when measuring gross tonnage?

Correct Answer: Option C — Cargo holds

Cargo holds are the primary revenue-generating spaces of a vessel and are therefore included in the calculation of gross tonnage. Exemptions under 46 CFR 69.53 are strictly limited to non-earning spaces like navigation areas, machinery, and crew accommodations, ensuring the gross tonnage reflects the vessel's total enclosed volume.