Which of the following is NOT one of the five types of special flood hazards?

The correct choice identifies "offshore currents" as not being one of the five types of special flood hazards. Special flood hazards are specifically defined conditions that increase the risk of flooding in a certain area and are associated with particular geographical or hydrological characteristics.

Closed basins, uncertain flow paths, and dam breaks are all relevant to flood risk and can significantly impact floodplain management. For example, closed basins can lead to rapid water accumulation since they do not have an outlet for drainage, potentially causing localized flooding. Uncertain flow paths refer to situations where the direction of water flow is not easily predictable, which can complicate flood risk assessment and management. Dam breaks can lead to catastrophic flooding downstream, making them a critical concern in floodplain management scenarios.

In contrast, while offshore currents can influence coastal conditions, they do not fit within the recognized categories of special flood hazards related to the NFIP's floodplain management criteria. Thus, identifying "offshore currents" as the answer highlights a distinction between true flood hazards and those that are more related to hydrodynamic conditions without direct implications for floodplain management.