A relational database has tables for PATIENT_DEMOGRAPHY and VITAL_SIGNS data collected during a visit.

In arelational database structure, each record in a table is uniquely identified by aprimary key. In this case, theVITAL_SIGNStable uses acomposite primary keyconsisting of:

Patient Identifier,

Visit Number, and

Vital Signs Parameter Name.

This means each record represents aunique measurement of a specific parameter (e.g., blood pressure, pulse)for a patient at a specific visit.

When joiningPATIENT_DEMOGRAPHYandVITAL_SIGNStables on thepatient identifier, the result set will includeone record for every combination of patient, visit, and parameter— i.e.,one record per patient per visit per vital sign parameter.

Therefore,option Ccorrectly describes the expected number of records.

Reference (CCDM-Verified Sources):

SCDM GCDMP, Chapter: Database Design and Build, Section 5.2 – Primary and Foreign Key Relationships in Relational Models

CDISC SDTM Implementation Guide, Section 5.3 – Observation-Level Data Structures

ICH E6(R2) GCP, Section 5.5.3 – Data Organization and Integration Principles