What check should be conducted on auxiliary lights?

The correct choice focuses on the importance of ensuring that all auxiliary lights function properly. This check is crucial for safety and visibility on the road. Auxiliary lights, which include fog lights, spotlights, or any additional lighting, enhance the driver's ability to see and be seen, particularly in low-light conditions or adverse weather. Confirming that these lights are operational helps prevent accidents that could occur due to inadequate lighting.

Additionally, while it might be important for lights to be the latest model or have manual adjustment capabilities, the primary concern during a pre-trip inspection is functionality. Ensuring that the lights are turned off during the day is relevant for conservation and compliance with certain regulations, but it doesn't directly address the essential functionality that impacts safety. Therefore, the focus of the check should be on whether all auxiliary lights are working as intended.