Why are blind spot mirrors essential for truck drivers?

Blind spot mirrors play a critical role in enhancing safety for truck drivers by helping to reduce blind spots and improve overall visibility. Trucks have larger blind spots due to their size, making it difficult for drivers to see vehicles or pedestrians that may be in close proximity, especially on the sides and rear. By utilizing blind spot mirrors, drivers can expand their field of vision, allowing them to detect obstacles or other road users that would otherwise remain hidden from standard mirrors. This improved visibility is crucial for safe maneuvers, changing lanes, and ensuring that the area around the truck is clear before making turns or executing other driving actions.

The other options, while they may have some relevance to truck operations, do not capture the primary function of blind spot mirrors as effectively as the correct answer. Parking assistance and cargo visibility are more secondary benefits, and determining vehicle height does not pertain to the purpose of blind spot mirrors. Therefore, the importance of blind spot mirrors lies predominantly in their ability to enhance safety by minimizing blind spots on the road.