Which resource defines how resources are accessed on a server?

• A. StructureMap
• B. CodeSystem
• C. CompartmentDefinition
• D. StructureDefinition

Answer: (C)

CompartmentDefinition defines how resources are accessed on a server. In FHIR, compartments model the context (such as a patient or an encounter) under which related resources are grouped. The CompartmentDefinition resource specifies which resource types participate in each compartment and how they reference the context, guiding what a server should expose and how searches or data retrieval should behave within that context. For example, in a patient compartment you can access resources that reference that patient, like Patient, Observation, or Condition, while in an encounter compartment you’d access resources linked to that encounter.

Other resources serve different roles: StructureMap is for transforming data between different structures, CodeSystem defines the codes used in coding systems, and StructureDefinition defines constraints and extensions to resources (i.e., profiles).