The correct answer isD. For aNEMA Size 2 motor controller, the appropriate conductor range is10 AWG to 4 AWG for 60°C rated cableand10 AWG to 6 AWG for 75°C rated cable. This matches the common NEMA controller terminal wire range used for Size 2 starters and controllers in industrial motor control applications.
In practical source inspection and shop verification, this matters because the inspector must confirm that the controller terminals are suitable for the intended field wiring and that the manufacturer's assembly, labels, and terminal data are consistent with the governing standard and purchase specification.
The API Guide for Source Inspection and Quality Surveillance of Electrical Equipment includesMotor Control Centersamong the major covered equipment categories for source inspection. The guide also makes clear that its focus is onsource inspection and quality surveillance activities, meaning verification of compliance with drawings, specifications, nameplates, and applicable referenced standards during manufacture and inspection. Since MCC buckets and NEMA motor controllers rely on proper terminal and conductor compatibility,option Dis the correct NEMA-aligned answer.