Which formats can FHIR be represented in actual data exchange?

• A. JSON
• B. XML
• C. RDF (Turtle)
• D. JSON, XML, and RDF (Turtle)

Answer: (D)

FHIR is designed to be flexible in how data is exchanged. The core idea is that a FHIR resource can be serialized into multiple formats to fit different systems and use cases. The two most common formats are JSON and XML, which are widely used for RESTful API data exchange because they are lightweight and easy to parse by many programming environments. In practice, clients and servers negotiate the representation using HTTP Accept headers (for example, requesting application/fhir+json or application/fhir+xml).

Beyond JSON and XML, FHIR also supports RDF representations to enable semantic web interoperability. The RDF/Turtle serialization maps FHIR resources into RDF triples, allowing data to be queried with SPARQL, integrated with other RDF data sources, and linked across datasets.

Because FHIR resources can be represented in JSON, XML, and RDF (Turtle) for actual data exchange, all three formats are valid, making the full answer correct.