Before reversing out of a driveway onto a street with foot traffic, what is the safest way to establish what is behind your vehicle?

Why D is correct

Direct vision beats every sensor, which is why the core backing technique is to turn and look through the rear window while the car moves, letting mirrors and cameras cover the sides. Cameras have blind zones low and wide — the exact height where a toddler or a shopping trolley lives — and screens lag reality by a frame or two. Reversing is the only manoeuvre where you steer against your direction of travel and where everything behind you is static or unpredictable, so the technique deliberately maximises real eyes-on contact with the space you are entering.

Why the other options are wrong

A. Reverse quickly so the vehicle spends the least possible time in motion

Speed makes backing more dangerous, not safer. Everything that goes wrong behind a reversing car goes wrong faster when the car moves quickly, and the whole manoeuvre is supposed to be conducted at walking pace with continuous re-checking.

B. Sound the horn for several seconds before beginning to move

The horn announces you to people who can hear it and does nothing about what you still cannot see. It supplements awareness; it cannot replace eyes on the space, and a horn is a poor substitute for a two-second look.

C. Trust the reversing camera and parking sensors to cover the whole area

Cameras and sensors are aids with documented blind zones at bumper height and at the edges of the field of view. A child behind the bumper sits precisely in the gap between sensor detection and screen edge, which is the scenario the look-over-the-shoulder method exists to close.

On the road

Leaving a friend's townhouse, you turn fully around in the seat, arm across the backrest, and reverse at a crawl — and a kid on a scooter crosses behind you, low, fast, exactly at screen-edge height. The camera never registered him. Your eyes through the rear glass did, a full second before his scooter would have met your bumper.

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