The left outside rear-view mirror should be adjusted so that you can see which part with minimal head movement?

• A. The horizon behind you
• B. The entire left lane
• C. The right side of your vehicle
• D. The left rear edge of your vehicle

Answer: (D)

The main idea here is to establish a quick reference point for where your car ends so you don’t have to turn your head a lot to check traffic beside you. When the left outside mirror is adjusted properly, you can see the left rear edge of your own vehicle in the mirror. That edge acts like a marker: if you know it’s right there in the mirror, you can judge how close a vehicle in the left lane is without twisting your head.

Seeing the left rear edge gives you a stable frame of reference for merging or changing lanes and helps you monitor that blind-spot area efficiently. If you only see the horizon or the road behind, you’d need to move your head more to locate traffic relative to your car, which takes longer and can increase risk. While it’s useful to know what’s behind in the mirror, the edge of your own car in the mirror is the best cue for minimizing head movement while still keeping an eye on nearby traffic.