What is a key advantage of using mirrors when driving a truck?

Using mirrors while driving a truck is crucial because they provide a broader view of the surroundings. Unlike a regular passenger vehicle, trucks have significant blind spots due to their size and design. Mirrors are essential tools that help drivers see not only the immediate area directly behind the vehicle but also to the sides and far behind it, which enhances overall safety.

This broader visibility allows drivers to be aware of other vehicles, pedestrians, and obstacles that might be present in their vicinity, thereby making informed decisions while changing lanes, merging, or making turns. The correct answer emphasizes the need for comprehensive awareness while operating large vehicles, where visibility is often limited.

The other choices do not relate to the primary function of mirrors, as they do not play roles in adjusting the radio, increasing speed, or improving fuel economy.