Which statement best distinguishes hazard, exposure, and vulnerability in geospatial risk assessment?

• A. Hazard is the probability of a harmful event occurring; exposure is the vulnerability of assets to that event; vulnerability is the actual losses.
• B. Hazard is the potential event; exposure is the number of assets in the area; vulnerability is the geographic distance to hazard source.
• C. Hazard is the potential event; exposure is the presence of people/assets in harm's way; vulnerability is the susceptibility to damage and loss given exposure and hazard.
• D. Hazard is the intensity of hazard; exposure is the time of day of impact; vulnerability is the response time.

Answer: (C)

In geospatial risk assessment, the three pieces describe different aspects of potential harm: hazard is the potential harmful event and its characteristics (what could happen, how severe, and how likely); exposure is the presence of people, property, or infrastructure in the area that could be affected; and vulnerability is how susceptible those assets are to damage or loss if the event occurs, given both the hazard and the exposed assets. The statement that best fits this concept says: the hazard is the potential event; exposure is the presence of people or assets in harm’s way; vulnerability is the susceptibility to damage and loss given exposure and hazard. For example, in a flood scenario, the hazard is the flood event itself (its magnitude and probability); exposure is how many and what value of buildings sit in the floodplain; vulnerability depends on how those buildings would perform under flood conditions (construction quality, elevation, flood defenses). The other options mix up these roles—for instance, treating vulnerability as actual losses, or treating exposure as a distance measure or time of day, or defining hazard only by intensity—which shifts focus away from the distinct meanings of each element.