Why is it important to adjust mirrors before driving?

Adjusting mirrors before driving is crucial for ensuring maximum rear visibility. Properly positioned mirrors enhance the driver's ability to see other vehicles, obstacles, and pedestrians behind and alongside the car, which is vital for safe maneuvering. This visibility helps in changing lanes, merging onto highways, and monitoring surroundings, significantly reducing the risk of accidents.

The other options do not relate to the primary functionality of mirrors in a vehicle. While improving radio reception or checking for traffic lights might be considerations for drivers, they do not pertain to the fundamental role of mirrors in promoting safe driving practices. Additionally, preventing car theft is more about securing the vehicle rather than visibility and awareness of the driving environment, which mirrors directly contribute to.