All inspected vessels on unrestricted ocean routes must have equipment on board for testing an individual's __________.

Correct Answer: Option B — breath

46 CFR 4.06-20 mandates that inspected vessels on unrestricted ocean routes carry equipment to conduct breath alcohol testing. This requirement ensures that the vessel can comply with mandatory post-accident testing protocols for crew members involved in a Serious Marine Incident, as breath testing is the primary field method.