Which space(s) is(are) deducted from gross tonnage to derive net tonnage?

Correct Answer: Option D — Boatswain's stores

Net tonnage is derived by subtracting non-earning spaces from gross tonnage. Under 46 CFR Part 69, spaces used for the exclusive use of the crew, including boatswain's stores, are considered exempt or deductible spaces, as they do not contribute to the vessel's revenue-generating capacity for cargo or passengers.