True statement about labeling:

• A. It helps identify circuits quickly during maintenance.
• B. It is optional and not needed.
• C. Labeling should be placed only on the exterior.
• D. It is unnecessary for safety.

Answer: (C)

Labeling circuits makes maintenance and service work safer and faster by letting you identify what each breaker controls at a glance. Placing the labeling on the exterior of the panel ensures that this information is readily visible from outside the enclosure, so technicians can quickly shut off or verify the correct circuit without opening the panel. While a directory inside the door is common, exterior labeling guarantees visibility and reduces the need to access the interior during routine checks or emergencies. Labeling isn’t optional and it directly supports safety by preventing wrong connections or accidental energizing. So, the statement that labeling should be placed only on the exterior aligns with the goal of making circuit identification immediately accessible.