What must a driver do before backing a vehicle without a guide?

Before backing a vehicle without a guide, it's essential for a driver to look for hazards and check clearances. This step is crucial because it ensures the driver is aware of their surroundings and can avoid obstacles, pedestrians, or other vehicles that may not be visible in the mirrors. By conducting a visual check of the area behind the vehicle, the driver mitigates the risks associated with backing up, which can often lead to accidents if not done carefully.

While other options involve checking the area in various ways, they do not fully encompass the thorough approach of actively ensuring that there are no hazards in the intended path of movement. This comprehensive assessment is a vital practice for maintaining safety while reversing a vehicle.