Why is it important to check blind spots before changing lanes?

Checking blind spots before changing lanes is crucial because it helps to avoid collisions with unseen vehicles. Blind spots are areas around a vehicle that cannot be directly observed by the driver while looking in the mirrors. When changing lanes, there could be vehicles, motorcycles, or bicycles occupying these blind spots. If a driver fails to check these areas, they may not see an approaching vehicle, leading to a dangerous situation that could result in an accident. By ensuring that the blind spots are clear, a driver can safely execute a lane change, significantly reducing the risk of collisions and enhancing overall road safety.

The other options, while relevant to driving, do not directly address the specific reason for checking blind spots when changing lanes. Gauging the speed of vehicles is important for safe merging and maintaining appropriate distance, but does not specifically prevent accidents that can occur from unseen vehicles. Allowing room for larger vehicles is also necessary, but it is less about blind spots and more about spatial awareness. Preparing for changing speed limits is a different aspect of safe driving and pertains to adjusting vehicle speed rather than visibility concerns.