What is a key reason for properly adjusting mirrors before driving?

Properly adjusting mirrors before driving is essential to avoid blind spots. Blind spots are areas around the vehicle that are not visible to the driver through standard mirrors. When mirrors are adjusted correctly, they provide a broader view of the surrounding area, including vehicles that may be in adjacent lanes or approaching from behind. This visibility is crucial for safe lane changes, merging, and overall awareness of one’s surroundings while driving.

Having mirrors positioned accurately helps ensure that the driver is aware of all vehicles and obstacles nearby, significantly reducing the risk of accidents that could occur due to undetected vehicles in blind spots. While the other options might present issues under different circumstances, they do not directly impact driving safety to the same extent as the ability to eliminate blind spots does.