The correct answer isC. One-line drawing. In switchgear inspection and acceptance testing practice, fuse ratings and circuit breaker sizes and types are verified against theapproved one-line drawing, because that document defines the electrical distribution arrangement, protective device coordination, feeder identification, equipment ratings, and the intended relationship between upstream and downstream protection. During source inspection and quality surveillance, the inspector must confirm that the installed protective devices match the project design documents and purchase requirements. The one-line drawing is the key reference used to verify whether the correct breaker frame, trip rating, fuse class, and protective arrangement have been provided.

The other options do not serve as the primary verification basis for protective device size and type. Atransformer nameplategives transformer data only, not the full protective scheme for the switchgear lineup.Shutter installation operationrelates to safety and mechanical function, not device sizing. Acurrent transformer turns ratiois associated with metering and protection circuits, but it does not determine the required fuse or breaker type for the overall lineup. Therefore, the proper reference for verifying fuse and circuit breaker sizes and types is theone-line drawing.