According to U.S. regulations, which of the following conditions would disqualify a nonmetallic hose as being suitable for use in transferring oil?

Correct Answer: Option C — Evidence of internal or external deterioration.

33 CFR 156.170 mandates that transfer hoses must be free of defects that could compromise integrity. Evidence of internal or external deterioration, such as soft spots, bulges, or exposed reinforcement, indicates the hose is no longer fit for service and must be removed to prevent catastrophic failure during oil transfer.